Legislative elections were held in France on 11 and 18 June 2017 to elect the 577 members of the 15th National Assembly of the Fifth Republic. They followed the two-round presidential election won by Emmanuel Macron. The centrist party he founded in 2016, La République En Marche! (LREM), led an alliance with the centrist Democratic Movement (MoDem); together, the two parties won 350 of the 577 seats—a substantial majority—in the National Assembly, including an outright majority of 308 seats for LREM. The Socialist Party (PS) was reduced to 30 seats and the Republicans (LR) reduced to 112 seats, and both parties' allies also suffered from a marked drop in support; these were the lowest-ever scores for the centre-left and centre-right in the legislative elections. The movement founded by Jean-Luc Mélenchon, la France Insoumise (FI), secured 17 seats, enough for a group in the National Assembly. Among other major parties, the French Communist Party (PCF) secured ten and the National Front (FN) obtained eight seats. Both rounds of the legislative election were marked by record low turnout.

The National Assembly is the lower house of the bicameral French Parliament under the Fifth Republic, the upper house being the Senate. The National Assembly's legislators are known as députés, meaning "delegate" or "envoy" in English; etymologically, it is a cognate of the English word deputy, the standard term for legislators in many parliamentary systems.