The 2017–18 season is San Lorenzo de Almagro's 33rd consecutive season in the top-flight of Argentine football.

The season covers the 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.

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