2017–18 Campionato Sammarinese di Calcio

The 2017–18 Campionato Sammarinese di Calcio was the 33rd season since its establishment.

It is the highest level in San Marino, in which the country's top 15 amateur football clubs played.

The season begin on 8 September 2017 and concluded with the play-off final on 23 May 2018.

The play-offs were played in a double-elimination format with both regular season group winners earning byes in the first and second round.

All matches were decided over one leg with extra time and then penalties used to break ties, when required.