Abstract: The present invention provides a thermostat with GFCI which includes control module, keyboard module, communication module and display module, and it further includes a leakage detection module, and the control module includes the temperature sensor, and the leakage detection module is connected with the control module, keyboard module and display module respectively. The control module is connected with the controlled device by the leakage detection module. The thermostat monitors current status of output circuit while adjusting the temperature of room, so that it can ensure the safety of the output circuit in use. If leakage occurs to the controlled device, the thermostat can cut off the power and stop power supplying at once, and the alarm light illuminates in the meantime. After manual reset, the alarm light goes out.