Cassine (Piedmontese: Cassèine) is a town and commune of the Province of Alessandria in the Italian region Piedmont.

It is located 21 kilometres (13 mi) southwest of the town of Alessandria on the left of the lower course of the Bormida in the Alto Monferrato Acquese.

Its economic character is agricultural: the hills are rich in vineyards where the wines Moscato d'Asti, Barbera and Freisa are produced as well as grappa.

In addition to the nucleus of Cassine itself (the capoluogo) three frazioni fall within the boundaries of the commune: Caranzano, Gavonata, and Sant'Andrea.

However, located at the edge of the Ghibelline marquisate, control of Cassine was contested by the Guelfs of Alessandria who conquered and destroyed the town in 1231 and subsequently exacted an annual tribute.