The utility model discloses a relay performance parameter extraction and fault early warning device used for a transformer cooling device. The relay performance parameter extraction and fault early warning device comprises a relay, a load circuit of the relay, a sensor module, a main control processing system and a display interface which are sequentially connected with one another, wherein the main control processing system comprises a host and a data acquisition board card, and the data acquisition board card is used for acquiring data output by the sensor module, and transmitting the data to the host. The relay performance parameter extraction and fault early warning device can relatively accurately and relatively quickly extract main performance parameters of the relay used for the transformer cooling device, and can effectively judge whether the relay used for the transformer cooling device has faults and judge the severity of the faults by comparing the extracted main performance parameters with the main performance parameters of the relay used for the transformer cooling device under normal operation.