The present utility model relates to submersible motor and its protector. A shared assembling base is provided to support and fix one end of the housing of the submersible motor and protector, the submersible motor has a main shaft to connect through the protector. The end of the assembling base connecting with the protector has a thrust bearing to support the motor shaft and form a thrust bearing chamber with the seal base of the protector, the shared assembling base has a cooling oil connecting passage, the isolation chamber where the bag is put in is formed between the seal base and assembly head base of the protector, a mechanical seal outside the assembly head base is provided for acting on the main shaft.