A microwave level switch is a level switch consisting of a transmitter and a receiver. The transmitter and receiver are installed face-to-face, with the transmitter emitting microwaves to the receiver. When the microwaves are obstructed by an object, the receiver outputs a relay signal. Adverse working conditions may cause the sensor surface to become dirty or covered with paper shreds and other materials. Due to the strong penetrability of microwaves, the sensor can easily penetrate these impurities to complete the measurement. Therefore, it can be effectively used to monitor the level of waste, ore, powder, granular materials, asphalt, and other media.