Senatorial elections were held on 24 September 2017 to renew 170 of 348 seats in the Senate of the French Fifth Republic.

The vacant series 2 seat in Savoie will be filled separately with a by-election also held on 24 September.

Delegates must be French nationals and be registered on the electoral list of the municipality in question.

Since the law on the accumulation of mandates of 14 February 2014, parliamentary mandates have been considered incompatible with local executive functions (president or vice-president of regional or departmental councils, mayor or deputies to mayors, and similar offices).

[1] Gérard Larcher was re-elected president of the Senate on 2 October 2017, challenged only by Didier Guillaume and Éliane Assassi.