Including sulfur hexafluoride detection unit, temperature detection unit and communication unit. Ultrasonic detection technology is used for sulfur hexafluoride detection. Imported ultrasonic sensors are used to overcome shortcomings such as short service life and poor stability. It can monitor SF6 in the environment in real time. The gas concentration changes, and the detected data values are uploaded in time through the RS485 communication bus. In addition to detecting sulfur hexafluoride, the SF6 gas detector also measures the ambient temperature in real time, and performs temperature compensation, which is not affected by the ambient temperature. The SF6 gas transmitter also has an automatic calibration function to overcome drift and error. Report, and self-diagnosis function.