The title of the utility model is a function detecting apparatus of an electrically-controlled gas mahcine double-channel sensor of a diesel engine and belongs to the technical field of automobile engine sensor detection. The function detecting apparatus is mainly characterized in that the function detecting apparatus comprises a four-layer frame, a liquid crystal display screen, a pneumatic control unit module, a clamp, and a cabinet main body, that a power supply and an industrial control computer are mounted in the cabinet main body, that the industrial control computer is connected with the power supply, the pneumatic control unit module, the liquid crystal display screen, a load, a operating keyboard, and the clamp through cables, that the clamp comprises a cylinder, a clamp pedestal, a clamp top rack, a clamp top cover plate, guide rails, buttons, and sensor fixing seats, that the two guide rails are respectively disposed on the two sides of the clamp pedestal, that the cylinder is fixed on the clamp top rack and is connected with the clamp top cover plate mounted on the two guide rails, and that the sensor fixing seats are disposed on the clamp pedestal and between the two guide rails. The function detecting apparatus has characteristics of fast testing speed, high precision, and suitability for large batch production, and is mainly used in the function detection of the Weichai electrically-controlled gas mahcine double-channel sensor.