A portable three-phase voltage transformer intelligent calibrating device has a portable box-type structure and comprises a three-phase program-controlled efficient power source (1), a three-phase booster synchronous boosting module, a microprocessor (2), a three-phase voltage transformer check module, and a three-phase program-controlled load module, all the modules utilize the microprocessor to conduct communication demand control on a secondary load (4) provided by a voltage transformer through an RS232 serial communication interface (3); the three-phase synchronous boosting module driven by the three-phase program-controlled efficient power source provides a controllable three-phase voltage to an external three-phase booster (5); the three-phase voltage transformer check module is a check module formed by a difference measuring circuit, and is respectively connected with secondary corresponding terminals of an external standard three-phase voltage transformer (6) and a tested three-phase voltage transformer (7); and the three-phase program-controlled load module is a program-controlled load box formed by combining noninductive resistors. The portable three-phase voltage transformer intelligent calibrating device is applicable to calibrating three-phase voltage transformers on site or in laboratories.