The French Socialist Party held a two-round presidential primary to select a candidate for the 2017 presidential election on 22 and 29 January 2017. It was the second open primary held by the center-left coalition, after the primary in 2011 in which François Hollande defeated Martine Aubry to become the Socialist nominee. Hollande went on to defeat incumbent Nicolas Sarkozy in the 2012 presidential election. However, because of his low approval rating, he announced that he would not seek re-election, becoming the first president of the Fifth Republic to decide not to run for a second term. The primary was contested by seven candidates, four from the Socialist Party and three representing other parties part of the left-wing electoral alliance.

The Socialist Party is a French centre-left and social-democratic political party. It holds pro-European views. The PS was for decades the largest party of the "French Left" and used to be one of the two major political parties in the French Fifth Republic, along with the Union for a Popular Movement. It replaced the earlier French Section of the Workers' International in 1969 and is currently led by First Secretary Olivier Faure. The PS is a member of the Party of European Socialists, Progressive Alliance and Socialist International.