A snow depth sensor based on the the phase method laser rangefinding is described from aspects of the sensor measurement principle, observation method, and data processing algorithm, which participated in the snow depth contrast observational experiments between such stations as Tonghe (Heilongjiang River), Altai (Xinjiang), etc., organized by the China Meteorological Administation in 2010 and 2011 The measurements are compared with the ultrasonic sensor and artificial measured snow depth data. The results indicates that this laser snow depth sensor can adapt to winter cold and Blizzard weather conditions well, can monitor snow surface changes continuously, automatically, and accurately; compared to the ultrasonic snow deep sensor, the laser snow depth sensor measurements are more stable and closer to artificial observation; the average difference between the laser snow depth sensor and artificial measurement snow deep results is about 1 cm, and the measurement precision reached the requirements of “Ground Meteorological Observation Specification”.