Giovanni Pacini (11 February 1796 – 6 December 1867) was an Italian composer, best known for his operas. Pacini was born in Catania, Sicily, the son of the buffo Luigi Pacini, who was to appear in the premieres of many of Giovanni's operas. The family was of Tuscan origin, living in Catania when the composer was born. He served as the Florence Conservatory's first director from 1849 through 1862.

His first 25 or so operas were written when Gioachino Rossini dominated the Italian operatic stage. But Pacini's operas were "rather superficial", a fact which, later, he candidly admitted in his Memoirs. For some years he held the post of "director of the Teatro San Carlo in Naples." Later, retiring to Viareggio to found a school of music, Pacini took time to assess the state of opera in Italy and, during a five-year period during which he stopped composing, laid out his ideas in his Memoirs. Like Saverio Mercadante, who also reassessed the strength and weaknesses of this period in opera, Pacini's style did change, but he quickly became eclipsed by the rising influence of Giuseppe Verdi on the Italian operatic scene, and many of his operas appeared to be old fashioned and rarely, if ever, appeared outside of Italy." Pacini's work is largely forgotten today, although some recordings do exist.