Francis Jean Marcel Poulenc (French: [fʁɑ̃sis ʒɑ̃ maʁsɛl pulɛ̃k]; 7 January 1899 – 30 January 1963) was a French composer and pianist. His compositions include songs, solo piano works, chamber music, choral pieces, operas, ballets, and orchestral concert music. Among the best-known are the piano suite Trois mouvements perpétuels (1919), the ballet Les biches (1923), the Concert champêtre (1928) for harpsichord and orchestra, the Organ Concerto (1938), the opera Dialogues des Carmélites (1957), and the Gloria (1959) for soprano, choir, and orchestra.

As the only son of a prosperous manufacturer, Poulenc was expected to follow his father into the family firm, and he was not allowed to enrol at a conservatoire. He studied with the pianist Ricardo Viñes, who became his mentor after the composer's parents died. Poulenc also made the acquaintance of Erik Satie, under whose tutelage he became one of a group of young composers known collectively as "Les Six". In his early works Poulenc became known for his high spirits and irreverence. During the 1930s a much more serious side to his nature emerged, particularly in the religious music he composed from 1936 onwards, which he alternated with his more light-hearted works.

In addition to his work as a composer, Poulenc was an accomplished pianist. He was particularly celebrated for his performing partnerships with the baritone Pierre Bernac (who also advised him in vocal writing) and the soprano Denise Duval. He toured in Europe and America with both of them, and made a number of recordings as a pianist. He was among the first composers to see the importance of the gramophone, and he recorded extensively from 1928 onwards.

In his later years, and for decades after his death, Poulenc had a reputation, particularly in his native country, as a humorous, lightweight composer, and his religious music was often overlooked. In the 21st century, more attention has been given to his serious works, with many new productions of Dialogues des Carmélites and La voix humaine worldwide, and numerous live and recorded performances of his songs and choral music.

Poulenc was born in the 8th arrondissement of Paris on 7 January 1899, the younger child and only son of Émile Poulenc and his wife, Jenny-Zoé, née Royer. Émile Poulenc was a joint owner of Poulenc Frères, a successful manufacturer of pharmaceuticals (later Rhône-Poulenc). He was a member of a pious Roman Catholic family from Espalion in the département of Aveyron. Jenny Poulenc was from a Parisian family with wide artistic interests. In Poulenc's view, the two sides of his nature grew out of this background: a deep religious faith from his father's family and a worldly and artistic side from his mother's. Claude Rostand later described Poulenc as "half-monk and half-naughty boy".

Poulenc grew up in a musical household; his mother was a capable pianist, with a wide repertoire ranging from classical to less elevated works that gave him a lifelong taste for what he called "adorable bad music". He took piano lessons from the age of five, initially from her; when he was eight he first heard the music of Claude Debussy and was fascinated by the originality of the sound. Other composers whose works influenced his development were Franz Schubert and Igor Stravinsky: the former's Winterreise and the latter's The Rite of Spring made a deep impression on him. At his father's insistence, Poulenc followed a conventional school career, studying at the Lycée Condorcet in Paris rather than at a music conservatory.

In 1916 a childhood friend, Raymonde Linossier (1897–1930), introduced Poulenc to Adrienne Monnier's bookshop, the Maison des Amis des Livres. There he met the avant-garde poets Guillaume Apollinaire, Max Jacob, Paul Éluard and Louis Aragon. He later set many of their poems to music. In the same year he became the pupil of pianist Ricardo Viñes. The biographer Henri Hell comments that Viñes's influence on his pupil was profound, both as to pianistic technique and the style of Poulenc's keyboard works. Poulenc later said of Viñes:

He was a most delightful man, a bizarre hidalgo with enormous moustachios, a flat-brimmed sombrero in the purest Spanish style, and button boots which he used to rap my shins when I didn't change the pedalling enough. ... I admired him madly, because, at this time, in 1914, he was the only virtuoso who played Debussy and Ravel. That meeting with Viñes was paramount in my life: I owe him everything ... In reality it is to Viñes that I owe my fledgling efforts in music and everything I know about the piano.