Water immersion sensor

The utility model discloses a water immersion sensor. The water immersion sensor includes a water leakage detection circuit and an alarm circuit. According to the water leakage detection circuit, an LM393 voltage comparator is adopted as a core chip; the LM393 voltage comparator and a resistance network are connected together so as to form the water leakage detection circuit; the water leakage detection circuit is connected with the alarm circuit consisting of a triode and a buzzer; the sensor can be powered by a battery or a 5V DC power source; and a probe interface, a power source input interface, a signal output interface and mounting positioning holes are reserved in the sensor. When a probe detects water leakage, the buzzer can be triggered to perform warning and signal output. The water immersion sensor is provided with various kinds of interfaces, and can be applied to various kinds of occasions, and has high practicability, and is especially suitable for underwater robot sealed cabins.