Paul Leppin was born in Prague on November 27, 1878, the second son of a poor Sudeten-German family. After completing secondary school, he began a career as a civil servant at the Postal and Telegraphic Office. His first novel, The Doors of Life was published in 1902. At this time Leppin was already an important figure in Prague literary circles, and was a spokesman of a younger generation of Prague German writers. Leppin, whose decadent lifestyle reflected his horror of bourgeois existence, was described by Max Brod as "the German-Bohemian Baudelaire." A scandal followed the publication of his novel Daniel Jesus (1905), which was considered blasphemous and obscene. By the first decade of the 20th century many of the writers Leppin was associated with, such as Rilke and Victor Hadwiger, had left Prague. Leppin stayed and his relationship to the city was expressed in several works, most famously his 1914 novel Severin's Journey into the Dark.

Severin, whose name is taken from the protagonist of Venus in Furs by Leopold von Sacher-Masoch, is tormented by his daily existence in the office and by the erotic chimeras he pursues by night. A similarly erotic theme is also at the center of his last work, the partly autobiographical novel Blaugast. Leppin suffered a series of personal tragedies in the 1930s, as well as receiving various recognitions for his life's work (e.g., the Schiller Memorial Prize in 1934). In 1937 his only son died, and in 1939 he was arrested and interrogated by the Gestapo after the Germans had occupied the city. Upon his release, he suffered a stroke that left him paralyzed. He died on April 10, 1945.