FSV Mainz 05 season is the 113th season in the football club's history and 9th consecutive and 12th overall season in the top flight of German football, the Bundesliga, having been promoted from the 2.

In addition to the domestic league, Mainz 05 also are participating in this season's edition of the domestic cup, the DFB-Pokal.

The season covers a period from 1 July 2017 to 30 June 2018.

Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.

Players may hold more than one non-FIFA nationality.