Abstract: To solve the heavy wear and poor life of thrust bearing in vertical motor because of its axial load long-term overload, the paper proposes a method that the axial load is offset by axial electromagnetic tension generated after the asynchronous motor rotor magnetized. Taking the vertical motor of condensed water pump in a 200 MW thermal power unit as example, the life of thrust bearing is calculated in the case of a part of axial loads on the axial magnetic force auxiliary. Experiment result shows that the method can lower the wear of thrust bearing and improve its life.