Selman Abraham Waksman (22 July 1888 – 16 August 1973) was an American biochemist and microbiologist whose research into organic substances — largely into organisms that live in soil — and their decomposition promoted the discovery of Streptomycin, and several other antibiotics. A professor of biochemistry and microbiology at Rutgers University for four decades, his work led to the discovery of over twenty antibiotics (a word which he coined) and procedures that have led to the development of many others. The proceeds earned from the licensing of his patents funded a foundation for microbiological research, which established the Waksman Institute of Microbiology located on Rutgers University's Busch Campus in Piscataway, New Jersey (USA). In 1952 he was awarded the Nobel Prize in Physiology or Medicine in recognition "for his discovery of "streptomycin" the first antibiotic active against tuberculosis."

In 2005 Selman Waksman was designated an ACS National Historical Chemical Landmark in recognition of the significant work of his lab in isolating more than fifteen antibiotics, including streptomycin, which was the first effective treatment for tuberculosis.

Selman Waksman was born on 22 July 1888 to Jewish parents in Nova Pryluka, Podolia Governorate in the Russian Empire, now Vinnytsia Oblast, Ukraine. He immigrated to the United States in 1910, shortly after receiving his matriculation diploma from the Fifth Gymnasium in Odessa, and became a naturalised American citizen six years later.

Waksman attended Rutgers College (now Rutgers University), where he was graduated in 1915 with a Bachelor of Science (B.Sc.) in Agriculture. He continued his studies at Rutgers, receiving a Master of Science (M.Sc.) the following year. During his graduate study, he worked under J.G. Lipman at the New Jersey Agricultural Experiment Station at Rutgers performing research in soil bacteriology. Waksman was then appointed as Research Fellow at the University of California, Berkeley, from where he was awarded his Doctor of Philosophy (Ph.D.) in Biochemistry in 1918.

Later he joined the faculty at Rutgers University in the Department of Biochemistry and Microbiology. It was at Rutgers that Waksman's team discovered several antibiotics, including actinomycin, clavacin, streptothricin, streptomycin, grisein, neomycin, fradicin, candicidin, candidin, and others. Two of these, streptomycin and neomycin, have found extensive application in the treatment of numerous infectious diseases. Streptomycin was the first antibiotic that could be used to cure the disease tuberculosis. Waksman coined the term antibiotics.

Many awards and honors were showered on Waksman after 1940, most notably the Nobel Prize in 1952; the Star of the Rising Sun, bestowed on him by the emperor of Japan, and the rank of Commandeur in the French Légion d'honneur.

Selman Waksman died on 16 August 1973 and was interred at the Crowell Cemetery in Woods Hole, Barnstable County, Massachusetts. His tombstone is inscribed simply as Selman Abraham Waksman: Scientist, followed by his dates of birth and death, and the phrase "The earth will open and bring forth salvation", which is a reference to Isaiah 45:8.

Waksman had been studying the Streptomyces family of organism since his college student days and had, for a time, been studying the organism Streptomyces griseus. Streptomycin was isolated from S. griseus and found effective against tuberculosis by one of Waksman's graduate students, Albert Schatz.

Waksman created the Waksman Foundation for Microbiology in 1951 using half of his personal patent royalties. At a meeting of the board of Trustees of the Foundation, held in July 1951 he urged the building of a facility for work in microbiology, named the Waksman Institute of Microbiology, which is located on the Busch campus of Rutgers University in Piscataway, New Jersey. The Selman A. Waksman Award in Microbiology of the National Academy of Sciences is given in his honor.