Equinoctial France (French France équinoxiale) was the contemporary name given to the colonization efforts of France in the 17th century in South America, around the line of Equator, before "tropical" had fully gained its modern meaning: Equinoctial means in Latin "of equal nights", i.e., on the Equator, where the duration of days and nights is nearly the same year round. The settlement was made in what is now known as the Bay of São Luis and lasted for 3 years.

The French colonial empire in the New World also included New France (Nouvelle France) in North America, extending from Canada to Louisiana, and for a short period (12 years) also included the colony of Antarctic France (France Antarctique, in French), in present-day Rio de Janeiro, Brazil. All of these settlements were in violation of the papal bill of 1493, which divided the New World between Spain and Portugal. This division was later defined more exactly by the Treaty of Tordesillas.