Gustave Kahn (Metz, France, December 21, 1859 - † Paris, France, September 5, 1936) was a French writer, poet and literary theorist who called himself the creator of the free verse.

Kahn began writing as a young man in Paris; He helped found and created several literary magazines, including La Vogue, Le Symboliste and La Revue Indépendante, along with Jean Moréas and Paul Adam, where his poems were published and several theories about the symbolist movement were fervently discussed.

His theories about free verse are explained in the preface to his book First Poems (1897), a collection that brings together his previous works Les palais nomades (1887), Chansons d´amant (1891) and Domaine de fée (1895).

Gustave Kahn broke with the Alexandrian tradition and sought that the prosody be less strict, so that the poetic rhythm depended more on the internal movement of the poem.