Born in Guadalajara, Jalisco, José Pablo Moncayo was introduced to music by his elder brother Francisco. Eduardo Hernández Moncadais is reported as the first teacher of José Pablo Moncayo in 1926, when the teenager was fourteen years old. According to Aurelio Tello, Hernández Moncada suggested his pupil Moncayo study at the National Conservatory. Tello reports that Moncayo was admitted to the conservatory in 1929; meanwhile, in order to finance his studies, he worked as a jazz pianist. According to the research of Torres - Chibrás, different sources point out the fact that Moncayo took composition lessons with Candelario Huízar, and it is known that he continued his piano instruction with Hernández Moncada. It is not certain in which courses Moncayo registered at the conservatory and who his other teachers were, but thanks to the biographies of his contemporaries Salvador Contreras, Blas Galindo and Daniel Ayala we may assume that Moncayo followed a similar path during his instruction at the National Conservatory. It is known that Huízar taught courses such as harmony, counterpoint and analysis (also called musical forms). Solfège or sight reading was taught by the eminent professors Vicente T. Mendoza and Gerónimo Baqueiro Foster. Music history was taught by Ernesto Enríquez. Luis Sandi was the conductor of the conservatory chorale and Eduardo Hernández Moncada, the associate conductor. In different periods Hernández Moncada taught, in addition to his piano lessons, harmony, sight reading, and later, opera ensembles. José Rolón, who had studied under Nadia Boulanger and Paul Dukas in Paris (and also met Arnold Schoenberg), taught harmony, counterpoint and fugue. Chávez was highly concerned with the general education and culture of the conservatory students and established literature courses taught by the contemporary poets Salvador Novo and Carlos Pellicer, world history by Jesús C. Romero, and history of Mexican culture by Agustín Loera and Chávez himself.

According to Salvador Contreras, Carlos Chávez created a composition course at the National Conservatory. Although Roberto García Morillo points out the year 1930, most sources agreed that this course started in 1931. According to Robert L. Parker, this new composition class was originally called Class of Musical Creation and later, Composition Workshop; Chávez had some colleagues as pupils, such as Vicente T. Mendoza, Candelario Huízar and Revueltas, and “there were four students under twenty years of age: Daniel Ayala and Blas Galindo (both pure blooded Indians), Salvador Contreras and José Pablo Moncayo.” Jesús C. Romero suggests that Chávez conducted a selection process among young students of the conservatory before admitting anyone and relates that Daniel Ayala was chosen thanks to his “incipient renown as composer, Salvador Contreras, for his violin skills, and José Pablo Moncayo, on account of his ability to do sight reading at the piano.” Furthermore, Romero reports that Blas Galindo was admitted the following year together with five other students. It seems that the new composition course attracted many students, their number increasing year after year, but only four of them attended the final examination. These four diligent students were Moncayo, Contreras, Galindo and Ayala. An article written by Galindo confirms his admittance to the course in 1932, together with seven other students. The article offers a detailed account of the training received at Chávez’s workshop.

At the first performance of the Renovation Musical Society (Sociedad Musical "Renovación") on August 22, 1931, Moncayo presented a couple of his own compositions, Impressions in a Forest, and Impression, both for solo piano. An opportunity of professional advancement for Moncayo in 1932 was his admission to the Symphony Orchestra of Mexico (OSM). The first program of the season of the Symphony Orchestra of Mexico dated 28 October 1932, lists the name of José Pablo Moncayo for the first time as a member of the orchestra in the percussion section.

During the fall of 1932, Chávez organized a festival of chamber music at the National Conservatory and invited his friend Aaron Copland to participate in it. The friendship between Chávez and Copland was extended to Revueltas as well, as described by Eduardo Contreras Soto, revealing that Revueltas also exchanged correspondence with the American composer. Moncayo and Galindo, both incipient proteges of Chávez, also started a long and fruitful relationship with Copland. Next year, Moncayo got a part time job as music teacher in a school (16 May 1933).

Mexican newspapers reported that on 1 December 1934, the new president of Mexico, General Lázaro Cárdenas, took the oath of office. There was a change in executive positions in the federal government, and Ignacio García Téllez, former dean of the National University, was now appointed Secretary of Education. García Téllez appointed José Muñoz Cota as chief of the Department of Fine Arts; as a result Chávez was removed from the head of the National Conservatory and was replaced by his enemy Estanislao Mejía. According to Blas Galindo, with the arrival of this new administration the composition workshop was terminated. Consequently, the composition training of Moncayo and his young friends was interrupted. According to Torres - Chibrás, "life was not easy at the conservatory for the four “orphans” of Maestro Chávez. Despite all the pressure exerted against them, they overcame all the difficulties, joined forces and emerged as an avant - garde group." Blas Galindo reports that they were branded as “Chavistas” and blacklisted by the new administration of the Conservatory, to the point of setting obstacles for their registration. They decided to give a first concert with their compositions demonstrating with it the truthfulness of the class of Music Creation that had been suppressed from the study plan of the Conservatory. The four friends agreed to arrange the program with compositions made by them after Chávez’s departure from the conservatory. On 25 November 1935, at 8:30 P.M., the first concert of these young composers took place at the Teatro de Orientación. Moncayo premièred his Sonatina for solo piano, performed by himself, and premiered as well Amatzinac, for flute and string quartet. His friends collaborated as performers in the following order: Salvador Contreras and Daniel Ayala, violins; Miguel Bautista, viola; Juan Manuel Téllez Oropeza, violoncello; and Miguel Preciado, as flute soloist. A review from José Barros Serra calls the students “The Group of Four,” with the aim to promote the nationalistic spirit of Mexican music. The second time these four young composers joined as a group was in a concert that took place on 26 March 1936, at 8:30 P.M. at the Teatro de Orientación. They adopted the epithet given to them the previous year in a newspaper review by José Barros Serra, the “Group of Four,” and this was the first public appearance where they intentionally used it. The Group of Four experienced increasing awareness among Mexican audiences and even some internationalization.

In the collection of programs of the year 1936 at the library of the National Arts Center, in Mexico City, José Pablo Moncayo is listed as a member of the percussion section of the controversial National Symphony Orchestra created in 1935 at the National Conservatory by Estanislao Mejía and conducted by Silvestre Revueltas from 1936 on. The OSM programs preserved at the Library of the National Center of the Arts have the program of 5 September 1936, where Moncayo’s La Adelita was premiered by the Orquesta Sinfónica de México, within the children’s concert series, under Carlos Chávez’s baton. One week later, on 11 September, Moncayo made his debut as orchestra conductor with the OSM, at the age of 24. During the seventh program of the season, Chávez gave Moncayo the opportunity to conduct the opening work of the evening, the Prelude of Richard Wagner's Lohengrin. Chávez conducted the rest of the program that included La damoiselle élue by Debussy, and Beethoven’s Ninth Symphony. The same month, in another program of the children’s concert series, the one of 26 September 1936, another arrangement by Moncayo, La Valentina, was premiered by the OSM, conducted by Carlos Chávez.

In 1941 Chávez organized a concert of Mexican music with the OSM that included some of the works presented during the previous year in New York and requested Moncayo and Contreras to write compositions for such a program. José Antonio Alcaraz says that, “It was Chávez himself who asked Moncayo to write a piece based on popular music of the (Mexican) southeast coast for a concert that he called ‘Traditional Mexican Music.' "

According to the notes prepared by Herbert Weinstock for the concerts arranged by Chávez in New York (1940), the program then included a work called Huapangos by Gerónimo Baqueiro Foster. This piece was in reality an orchestral arrangement of several popular dances from the eastern state of Veracruz. In the 1941 program Chávez replaced Baqueiro’s Huapangos with a new work called Huapango, written by Moncayo. The difference is that Moncayo’s Huapango is not just an arrangement but a legitimate work inspired by the popular music of Veracruz ("El Siquisiri", "El Balajú" and "El Gavilancito"). Chávez sent Moncayo and Galindo to Veracruz for a field exploration about the popular music of the region. Quoted by Moncayo's faithful pupil, José Antonio Alcaraz, Moncayo reports his experience:

Blas Galindo and I went to Alvarado, one of the places where folkloric music is preserved in its most pure form; we were collecting melodies, rhythms and instrumentations during several days. The transcription of it was very difficult because the huapangueros (musicians) never sang the same melody twice in the same way. When I came back to Mexico, I showed the collected material to Candelario Huízar; Huízar gave me a piece of advice that I will always be grateful for: “Expose the material first in the same way you heard it and develop it later according to your own thought.” And I did it, and the result is almost satisfactory for me.

Moncayo’s Huapango was premièred on 15 August 1941, at the Palace of Fine Arts by the Symphony Orchestra of Mexico under Chávez’s baton. Programs of the 1942 season list Eduardo Hernández Moncada as assistant conductor and José Pablo Moncayo at the piano as well as in the percussion section. Moncayo began to work on an ambitious project, a symphony. That summer, and probably thanks to the recommendations of Chávez and Copland, Moncayo and Galindo were granted scholarships from the Rockefeller Foundation to study at the Berkshire Music Institute, known today as the Tanglewood Music Center. According to Dr. Jesús C. Romero, Moncayo was invited to attend there by Aaron Copland and Serge Koussevitzky. The Symphony was scheduled to be premiered by the Orquesta Sinfónica de México on 21 August 1942, but the performance was postponed. The première would take place a couple of years later. The program notes of 1 September 1944, written by Francisco Agea, explain that the two last movements were written in Berkshire:

Both movements were written in the United States, when Moncayo, invited by the director Serge Koussevitzky, attended the Berkshire Festival and the special courses taught to the new generations of composers. It is evident that the author, finding himself abroad and longing for his fatherland, felt the need to express himself in a Mexican language.

Moncayo worked in Berkshire not only on his symphony but also completed another work, probably in Copland’s composition course, Llano Grande for chamber orchestra, which was premiered by the orchestra during the Berkshire Festival precisely on 21 August. Arroyos by Blas Galindo, Moncayo's alter ego in this trip, was premiered in Berkshire a few days before, on 17 August. The two Mexicans also had the opportunity to meet two other fellow composers and conductors who attended the courses at Berkshire that summer, Lukas Foss and twenty - four year old Leonard Bernstein. Galindo reports his experiences about Berkshire:

There I meet Bernstein, who was kilometers ahead of me, Lukas Foss . . . I remember Hindemith who was very serious. I also met Latin American composers like Ginastera . . . [about Varèse] I have photos and autographed scores of his. I liked to go visit his studio in New York [City]; his compositions amazed me. He was building his techniques out of noises. I admire him because he dared to break with traditions, he was a pioneer. He knew that I cared about him.

The programs of 1945 reveal that Moncayo was appointed assistant conductor of the Symphony Orchestra of Mexico in that year and that his activities as conductor increased. The year 1946, the rising conducting career of Moncayo brought him to his next position. Chávez appointed the thirty - four year old conductor as artistic director of the Symphony Orchestra of Mexico, while Chávez remained its musical director.

Since it was not my intention to interrupt my achievement (the OSM), but that it continue under the responsibility of the Board of the Symphony and the competent and able technicians that they would recruit, I had no other choice but to remain as director of the orchestra, with the greatest and best desire that the new artistic director that we selected to formally work beside me, José Pablo Moncayo, would arrive to take full responsibility of the situation.

However, the Symphony Orchestra of Mexico season program of 1948 (13 February to 25 April) no longer lists Moncayo as a member of the orchestra. In 1948 Eduardo Hernández Moncada was the conductor of the National Symphony Orchestra (Mexico) (OSN) — created in 1947 under the aegis of the National Institute of Fine Arts — and within the programs Moncayo’s name appears on the list of musicians as the orchestra pianist. Chávez, as general director of the Fine Arts Institute, appointed Moncayo as music director / conductor of the National Symphony Orchestra (Mexico) on 1 January 1949.

The last program found with Moncayo’s name as conductor of the OSN dates from Wednesday 17 February 1954. It was a memorial concert held at the Palace of Fine Arts to honor a distinguished music professor, Don Luis Moctezuma, recently deceased. The program consisted of some words of appraisal by Andrés Iduarte, General Director of the INBA, Three Pieces for Orchestra by Moncayo, the Concerto for Three Pianos and Orchestra by J.S. Bach, an address by professor Manuel Bermejo Chibrás, followed by Piano Concerto No. 2 by Rachmaninoff. This was the last time in his life Moncayo conducted the National Symphony Orchestra of Mexico. His name never again appeared on a program of the OSN.

On 16 June 1958, Moncayo died in his home, at 295 Amsterdam Avenue, Mexico City, only a few days before his forty - sixth birthday.

José Pablo Moncayo is best known as the author of Huapango, a bright, short symphonic piece that is sometimes included in pop concerts by American orchestras. Scholarly research about this composer in the United States is still scarce today. Despite being highly regarded in his own country, Moncayo has been the subject of scant academic research, restricted to some program notes; magazine, newspaper and journal articles; and short paragraphs in music dictionaries and encyclopedias. Although the major contribution of Moncayo to Mexican music has been in the field of composition, he also played a relevant role in the national stage of culture during the ten years of his short conducting career (1944 – 1954). As orchestra conductor, his promising career was hampered by a difficult cultural environment, political situations and premature death. According to Torres - Chibrás, José Pablo Moncayo’s career as an orchestra conductor is a subject that has not been exhausted by Mexican or foreign scholars. José Antonio Alcaraz, musicologist and leading music critic of Mexico, assesses that: Mexican nationalism vigorously encompasses a period whose chronological limits may be fixed for study purposes with some precision in 1928: the year of the founding of the Symphony Orchestra of Mexico and ending three decades later, in 1958 with the death of José Pablo Moncayo, a composer born in 1912.

Moncayo’s death coincides with the decline of the Nationalist movement resulting from the demise of the ideals of the Mexican Revolution. Yolanda Moreno Rivas concludes: The death of Moncayo in 1958 tangibly marked the end of the Mexican nationalist composition school. In the same way that his work without followers surpassed and abolished the innocent use of the Mexicanism theme, his death closed the predominance of a composition style whose imprint marked musical creation in Mexico during more than three decades; although only at the beginning of the sixties would it be possible to talk about the definitive abandonment of the great Mexican fresco, the oblivion of the epic tone, and the search for new structural factors in composition.

Moncayo's best known work continues to be his colorful orchestral fantasy Huapango (1941), but his production also includes many other pieces of a high quality, notwithstanding their lesser fame. Among these are works like Amatzinac for flute and string quartet (1935); his Symphony (1944); Sinfonietta (1945); Homenaje a Cervantes for two oboes and string orchestra (1947); his opera La Mulata de Córdoba (1948); Tierra de Temporal (1949); Muros Verdes for piano solo (1951); Bosques (1954); and the ballet Tierra (1958).