The Exposition Universelle of 1855, better known in English as the 1855 Paris Exposition, was a world's fair held on the Champs-Élysées in Paris, France, from 15 May to 15 November 1855. Its full official title was the Exposition Universelle des produits de l'Agriculture, de l'Industrie et des Beaux-Arts de Paris 1855. It was the first of ten major expositions held in the city between 1855 and 1937. Nowadays, the exposition's sole physical remnant is the Théâtre du Rond-Point des Champs-Élysées, designed by architect Gabriel Davioud, which originally housed the Panorama National.

A world's fair, also known as a universal exhibition or an expo, is a large global exhibition designed to showcase the achievements of nations. These exhibitions vary in character and are held in different parts of the world at a specific site for a period of time, typically between three and six months.