The invention relates to a method and apparatus for testing vehicle combination instrument which is tested comprehensively and reasonably by imitating the vehicle state. The technical solution is that the method for testing vehicle combination instrument comprises: outputting resistance test signals imitating a fuel and water temperature sensor; outputting frequency test signals imitating a vehicle speed and rotating speed sensor through a frequency signal generating unit, and PWM test signals imitating the water temperature sensor; transmitting the test signals to the combination instrument for test.