Wind sensors of automatic meteorological station are frequently frozen and fail to work. To resolve the problem, an automatic malfunction detecting device based on the ZQZTF wind sensor is designed for the realtime detection of freezing faults. By detecting working voltage and current, the proposed device is able to keep the sensors under surveillance. In addition, combined with the specific diagnosis algorithm, it is quick to distinguish whether the wind sensors are frozen or not. The hardware circuit and software algorithm of the design can be integrated in the wind speed data acquisition circuit and the embedded software of the automatic meteorological station respectively. It allows for compact structure and simplified operation. It has been demonstrated that the device is competent for the realtime detection of frozen sensors, and it works stably with high detection precision as well.