The invention discloses a voltage transformer calibration method. According to the method, the primary wiring end of a three-phase voltage regulator is connected into a fuse I, a fuse II and a fuse III separately; the other ends of the fuse I, the fuse II and the fuse III are connected to a three-phase alternating-current contactor separately, and the other end of the three-phase alternating-current contactor is connected with a 380V alternating-current power supply; a secondary wiring end of the three-phase voltage regulator is connected to primary A, B and C wiring ends of the voltage transformer separately; a voltmeter I is connected between the wiring end A and the wiring terminal B, and a voltmeter II is connected between the wiring end B and the wiring terminal C; a voltmeter III, avoltmeter IV and a voltmeter V are connected between the a, b and c wiring ends of the secondary first winding of the voltage transformer and a null potential respectively; and a voltmeter VI is connected between the d and a wiring ends of the secondary second winding of the voltage transformer and the null potential, and then verification is carried out. The method has the advantages that the steps are simplified, the test is convenient, the working efficiency is improved, and the safe production is guaranteed.