Abstract: The flame-proof asynchronous motor used in conveyor often works in the state of no-load, light load and overload.It causes the changes of current and the loss of stator and rotor, which will influence the temperature rise and the reliable operation of the motor.In this paper, taking YBSD-525/263-4/8G motor as an example, the two-dimensional finite element model was established.The motor loss was analyzed in three running state.Through the analysis of copper loss, it showed that the current of the stator and rotor increased with the load increase.The harmonic current also increased.It leaded the increase of copper loss.When the iron loss was analyzed, the iron core was divided into seven parts in order to reduce the impact of flux density distribution.The analysis result showed that the iron losses in the tooth top and tooth body increased fast and the change of the iron loss in the tooth root and tooth yoke was not big with load increase.This study provided a foundation for analyzing the temperature field of the motor with load states change.