Abstract: During the operation process of the motor, a large amount of heat is generated, leading to excessive temperature rise. The internal loss problem is an important factor affecting the temperature rise of the motor. The losses in the motor mainly include four types: copper loss, iron loss, mechanical loss, and stray loss. Firstly, based on the four types of losses, analysis is conducted from the aspects of loss causes, loss calculation, loss impact, and consumption reduction methods. The calculation methods for the four types of losses are studied, with focus on introducing the calculation and analysis methods for motor iron loss. Secondly, based on the factors affecting losses, the feasibility of the consumption reduction method is determined by optimizing design of the motor structure. The accurate analysis of motor losses is of great significance for analyzing motor temperature rise issues and designing low loss and high-efficiency motors.