Beardsley was aligned with the Yellow Book coterie of artists and writers, and produced many illustrations for the magazine. He was also closely aligned with Aestheticism, the British counterpart of Decadence and Symbolism.

Most of his images are done in ink, and feature large dark areas contrasted with large blank ones, and areas of fine detail contrasted with areas with none at all.

Aubrey Beardsley was the most controversial artist of the Art Nouveau era, renowned for his dark and perverse images and the grotesque erotica, which themes he explored in his later work. His most famous erotic illustrations were on themes of history and mythology, including his illustrations for Lysistrata and Salomé.

Beardsley was a close friend of Oscar Wilde and illustrated his play Salomé in 1893 for its French performance; it was performed in English the following year. He also produced extensive illustrations for books and magazines (e.g. for a deluxe edition of Sir Thomas Malory's Le Morte d'Arthur) and worked for magazines like The Savoy and The Studio. Beardsley also wrote Under the Hill, an unfinished erotic tale based loosely on the legend of Tannhäuser.

Beardsley was also a caricaturist and did some political cartoons, mirroring Wilde's irreverent wit in art. Beardsley's work reflected the decadence of his era and his influence was enormous, clearly visible in the work of the French Symbolists, the Poster Art Movement of the 1890s and the work of many later-period Art Nouveau artists like Pape, Mucha and Clarke.

Beardsley was a public character as well as a private eccentric. He said, "I have one aim — the grotesque. If I am not grotesque I am nothing." Wilde said he had "a face like a silver hatchet, and grass green hair."

Although Beardsley was aligned with the homosexual clique that included Oscar Wilde and other English aesthetes, the details of his sexuality remain in question. Speculation about his sexuality include rumours of an incestuous relationship with his elder sister, Mabel, who may have borne his miscarried child.

Beardsley died of tuberculosis in Menton, France at the age of 25 on March 16, 1898.