Le Ventre de Paris [lə vɑ̃tʁ də paʁi] (1873) is the third novel in Émile Zola's twenty-volume series Les Rougon-Macquart. It is set in and around Les Halles, the enormous, busy central market of 19th-century Paris. Les Halles, rebuilt in cast iron and glass during the Second Empire was a landmark of modernity in the city, the wholesale and retail center of a thriving food industry. Le Ventre de Paris (translated into English under many variant titles but literally meaning The Belly of Paris) is Zola's first novel entirely on the working class.

The protagonist is Florent, an escaped political prisoner mistakenly arrested after the French coup of 1851. He returns to his half-brother Quenu, a charcutier and his wife Lisa Quenu (formerly Macquart), with whom he finds refuge. They get him a job in the market as a fish inspector. After getting mixed up in an ineffectual socialist plot against the Empire, Florent is arrested and deported again.

Although Zola had yet to hone his mastery of working-class speech and idioms displayed to such good effect in L'Assommoir, the novel conveys a powerful atmosphere of life in the great market halls and of working class suffering. There are a number of vivid descriptive passages, the most famous of which, his description of the olfactory sensations experienced upon entering a cheese shop, has become known as the "Cheese Symphony" due to its ingenious orchestral metaphors. Throughout the book, the painter Claude Lantier, a relative of the Macquarts and later the protagonist of L'Œuvre (1886) - shows up to provide a semi-authorial commentary, playing the role of chorus. It is an interesting and often powerful work, though not usually considered as being on a par with the novelist's achievements later in the Rougon-Macquart cycle.