An artificial knee joint is to be connected between a prosthetic thigh and a prosthetic lower leg. The artificial knee joint includes a knee joint body, a processor mounted in the knee joint body, a damping unit that is coupled to the processor and configurable to provide various damping levels, and an accelerometer coupled to the processor. The accelerometer is configured to measure acceleration subjected to the artificial knee joint, and to generate and transmit a measuring signal according to the measurement to the processor. The processor is configured to control the damping unit to provide one of the damping levels, based on the measuring signal.