Born in Toulouse, France, on 22 October 1882, Edmond Dulac was the only child of Pierre Henri Aristide Dulac and Marie Catherine Pauline Rieu. The boy grew up in a comfortable petit bourgeois home. Educated at the Lycée de Toulouse, Dulac showed an early introversion and talent for drawing. By age sixteen he was able to render professional art nouveau work. After studying law at the University of Toulouse for two years, Dulac enrolled full time at the École des Beaux Arts in 1900. There he roomed with close friend and fellow student Émile Rixens. In 1903 Dulac won a scholarship to the Académie Julien in Paris. His December 1903 marriage to Alice May de Marini, an American thirteen years his senior, quickly dissolved and by 1904 he had left for England to start his artistic career. Enamored of British culture, he changed the spelling of his first name to Edmund.

Dulac was an immediate success in England. He joined the London Sketch Club soon after his arrival and later St. John's Art Club. His first commission was the illustration of , a quintessentially British project with which he was entrusted at the age of twenty-two. In April 1911 he married Elsa Arnalice Bignardi, a shy, graceful girl of Italian and German descent.

Dulac is best known as an illustrator of gift books and children's books. His favorite medium was watercolor. From 1890 to 1920, British book illustration was preeminent and Dulac's career flourished. He also collaborated with his friends W. B. Yeats and Sir Thomas Beecham on various theater projects. In 1920 he composed music for a production of Yeats's . Yeats, Dulac, and Ezra Pound staged Japanese Nō plays, with Dulac designing costumes, sets, and makeup and composing music.

The hardships of World War I were still keenly felt by 1920, a year which signaled the death of the gift book and the start of Dulac's financial insecurity. In the same year stopped running Dulac's cartoon drawings, which had been his only steady source of income. Though he managed on income from portraits and frequent commissions for covers and postage stamps, money was always to be a concern. In August 1923 Dulac and Elsa separated, Dulac complaining that she was unable to challenge him intellectually. Close friend Helen de Vere Beauclerk apparently was his equal in this respect, however, and she moved in within the year. She was to be Dulac's companion until his death.

Yeats dedicated to Dulac in 1933. In 1937 Dulac collaborated with Yeats on the BBC radio program, . Yeats selected seven of his own poems, five to be spoken and two to be sung, with Dulac composing music for the songs, accompaniment for the spoken poems, and interludes between. Partly owing to the intervention of the producer in the choice of performers, the performance did not come up to either man's expectations, with Yeats feeling that the singing style and accompaniment were not true to his vision and Dulac feeling that the two sung pieces were the only bright spots in a performance that Yeats had sabotaged in rehearsal. Hostilities flared briefly but were soon smoothed over. Yeats died on 28 January 1939 and was buried in France; when his body was reinterred in his native Ireland after the war, Dulac designed the memorial for his friend's former resting place in Roquebrune.

By World War II, Dulac had become the leading authority on postage stamp design. When occupied France wanted to unify its colonies against Germany by issuing stamps with the Cross of Lorraine, this project naturally fell to an enthusiastic Dulac. The project was commissioned by Charles de Gaulle, who travelled to Britain to discuss the matter. Dulac's wartime work culiminated in the Victory stamp for France, using Léa Rixens, Émile Rixens's widow, as the model for Marianne de Londres. For once he used the French spelling of his name in his signature: Edmond Dulac.

At the close of his career, Dulac returned to illustrating children's books with the same perfectionism that had characterized the rest of his work. He was in the middle of one such project when he had his third heart attack and died 25 May 1953, at the age of seventy.