Giuseppe Giacosa (21 October 1847 – 1 September 1906) was an Italian poet, playwright and librettist.

He was born in Colleretto Parella, now Colleretto Giacosa, near Turin. His father was a magistrate. Giuseppe went to the University of Turin, studying in the University of Turin, Faculty of Law. Though he gained a degree in law, he did not pursue a legal career.

He gained initial fame for his play Una Partita a Scacchi ("A Game of Chess") in 1871. His main field was playwriting, which he accomplished with both insight and simplicity, using subjects set in Piedmont and themes addressing contemporary bourgeois values. He wrote La Dame de Challant for noted French actress Sarah Bernhardt, which she produced in New York in 1891.

He also wrote the librettos used by Giacomo Puccini in La bohème, Tosca and Madama Butterfly in conjunction with Luigi Illica.