The Werribee River is a perennial river of the Port Phillip catchment that is located on the plain West of Melbourne, Victoria, Australia. The headwaters of a tributary, the Lerderderg River, are north of Ballan near Daylesford and it flows across the basalt plain, through the suburb of Werribee to enter Port Phillip.
A linear park follows the Werribee River along much of its course. In total the Werribee River completes a journey of approximately 110 kilometres. The river flows through the Werribee Gorge State Park before being utilised for irrigation of market gardens at Bacchus Marsh, then through Werribee where it is crossed by the Maltby By-pass. It then flows through the Werribee Open Range Zoo in Werribee Park, and finally the small coastal settlement of Werribee South before entering Port Phillip.