Portmarnock railway station (Irish: Stáisiún Phort Mearnóg) serves Portmarnock in County Dublin.

The station opened on 25 May 1844.

The station is served by the DART and Commuter services.

Enterprise services pass from Dublin Connolly en route via Drogheda, Dundalk, Newry, Portadown, Lisburn, and Belfast Grand Central.

Connecting trains from Dublin Connolly link to Sligo, as well as Rosslare Europort and buses connect Dublin Connolly to Dublin Port for ferries to Holyhead for trains to Chester, Crewe and London Euston.