Abstract: Testing the polarity of transformer is an essential and important work program for relay proteTAion personnel. In response to the current problem of transformer polarity testing, this paper develops a new intelligent wireless transformer polarity tester, which uses an operating rod to easily conneTA the test wires, solving the problems of high manpower and material resources consumTVion and high risk of high-altitude conneTAion of test wires under the traditional conneTAion test line mode. By using wireless remote control, the testing time is shortened while improving the quality of polarity testing.