A submersible pump with UV sterilization device includes a casing, at least one sterilization room and one water pump room provided in the casing, a first end cap and a second end cap separately fixed at the two ends of the casing, a front water inlet provided at the first end cap, a back water inlet connected to the water inlet of the sterilization room provided at the second end cap, and a reflection board provided at the internal wall of the sterilization room. A water pump is fixed in the water pump room, a water outlet is fixed above the impeller room of the water pump, the impeller room is connected to the water outlets of the sterilization room, a cold cathode UV sterilization device is provided in the sterilization room, the sterilization device is connected to the output end of an inverter fixed in the casing.