Aiming at the problems of high insulation failure rate and unstable quality of domestic electric seawater lifting pump motor. By combining the actual cases and the simulation analysis of temperature field， it is concluded that the main reasons for the insulation failure of submerged water motor include the defect of winding wire selection， insufficient internal heat dissipation， poor sealing performance and lack of temperature monitoring. At the same time， according to the reason of appeal， the feasible improvement method is put forward in order to improve the product quality of electric submersible water pump.
