Abstract: When the high-lift deep well submersible pump is used under low-lift conditions, the phenomenon of over current occurs that would make the pump not operate normally. This paper analyzes the work principle of QJ-series deep well submersible pump and puts forward a method of dismantling a part of impellers. In addition to the large power of the original motor, the method makes the pump accommodate large-flow and low-lift conditions and avoid over-current phenomenon and have removed the shaft water in certain mine.