A clutch hydraulic system for a vehicle wherein it is possible to independently operate two systems, to increase the degree of freedom in designing, and to achieve a reduction in cost. A seesaw member for transmitting motive power is provided between a second release cylinder and a first master cylinder, the first master cylinder and a second hydraulic oil pipe communicate with each other through a large diameter hole and a small diameter hole provided as communicating passages through which oil flows. A reservoir tank is provided for reserving the oil for controlling the amounts of the oil in the hydraulic oil passage on the side of the first master cylinder and the amount of the oil in the hydraulic oil passage on the side of the second release cylinder is connected to a second master cylinder.