A drive system for a vehicle includes an engine, a transmission, a clutch mechanism including first and second clutch portions, the clutch mechanism being switchable between connected and disconnected states, and a clutch operation mechanism switching the clutch mechanism between the connected and disconnected states, the clutch operation mechanism including a clutch drum forming a drum chamber, a piston dividing the drum chamber into a spring chamber and a pressurizing chamber, a control valve, a biasing member arranged in the spring chamber and exerting a biasing force in a direction in which the first and second clutch portions are engaged with each other, and a bore formed in the clutch drum, the bore discharging oil of the spring chamber to an outer side of the spring chamber in a state where a counteracting force against a centrifugal force acting in the pressurizing chamber is generated in the spring chamber.