The faucet of cartridge has an expandable temperature regulating rod in the main body. The temperature of water is regulated by changing the ratio of cold water and hot water by the movement of the temperature regulating rod. The water can be switched on or off by rotating the main body with respect to the seat. The main body includes an outer body, an inner body, and an anti-leaking element. The anti-leaking element is sandwiched between the outer body and the inner body to partition the space therebetween into two channels for cold and hot water to flow into the inner body.