It is served by lines S1, S2, S5, S6, and S7 of the Metro del Vallès commuter rail system, which are operated by Ferrocarrils de la Generalitat de Catalunya (FGC), who also runs the station.

[2] Sant Cugat is the last station before the Metro del Vallès branches to Terrassa (lines S1 and S5) and Sabadell (lines S2 and S55) split and take different routes.

Sant Cugat is also the outer terminus of some trains on line S5.

Immediately to the north of the station is a flat junction between the two branches.

Beyond this junction, between the tracks of the Sabadell branch, is a siding used to reverse trains on line S55.