A high-voltage grid comprehensive protector tester is characterized in that a circuit structure of the tester comprises a power supply circuit, a voltage analog circuit and a current analog circuit to generate in a simulative manner work voltage and work current of the high-voltage grid encountering with overload, short, overvoltage and under voltage and to generate in a simulative manner zero sequence voltage and zero sequence current for a GZBD leakage failure simulation; the circuit structure also comprises a timing stopwatch used for recording the failure action time of the comprehensive protector, a test function selection switch used for selecting a function from various failure test functions, a GZBD, DZBD test selection switch, an output relay used for generating in a simulative manner a ground leakage potentiometer W4 of ground leakage impedance. The invention can totally simulate high-voltage vacuum power distribution devices, low-voltage feeding switches and power supply circuits and second-time wiring of protecting boxes to lead the comprehensive protector to test and check all the parameters and capabilities even without a main unit.