A detection system and method for rotor dynamic turn-to-turn short circuit fault of synchronous generator are disclosed. The system includes a motor, a synchronous generator, a current transformer, an acquisition card, an infrared temperature sensor, a temperature acquisition instrument and a control terminal. The rotor winding dynamic turn-to-turn short circuit fault of synchronous generator is detected and located by measuring the double judgment standards of the temperature signal of rotor winding and the three-phase current signal of stator winding. The method is easy to operate and has high sensitivity. The detection and location process of the fault is efficient and reliable. The dynamic turn-to-turn short circuit fault can be detected in the early stage of the formation of rotor static turn-to-turn short circuit, so as to reduce the loss of power plant fault shutdown and better meet the needs of practical application.