The river Tordera (Catalan: La Tordera) is a river of Catalonia (Spain).
The river is 55 km long and has its source at Montseny massif, and its mouth in the Mediterranean Sea, and an average discharge of 5.01 m³/s.
Its main tributaries are the Riera de Gualba, Riera de Arbúcies, Riera de Santa Coloma and the Riera de Valmanya and it runs through the Parc Natural del Montseny and the Parc Natural del Montnegre i el Corredor.