Trezzano sul Naviglio (Milanese: Trezzan sul Navili or simply Trezzan [treˈsãː (syl naˈʋiːli)]) is a comune (municipality) in the Metropolitan City of Milan in the Italian region Lombardy, located about 9 km (6 mi) southwest of Milan.
Trezzano sul Naviglio borders the municipalities of Buccinasco, Cusago, Cesano Boscone, Corsico, Gaggiano, Milan, and Zibido San Giacomo. It is served by Trezzano sul Naviglio railway station.