Aiming at the problem of potential safety hazards of in-wheel motor (IWM) in fault condition for electric vehicle (EV) with a multitude IWMs drive, which is known as IWM-DEV, a more comprehensive approach is proposed to evaluate the operation safety of each IWM based on vehicle operation information. Firstly, the working principle and common electrical faults of IWM are introduced to establish the normal model and electrical fault simulation model that fault degree can be controlled, and the fault characteristics of IWM in different operation conditions are deeply analyzed. Secondly, a dynamics model of IWM-DEV with single or multiple IWMs in electrical fault condition is built on the basis of Matlab/Simulink and CarSim. The number, location, and degree of IWM’s fault are considered to quantitatively analyze the vehicle operation information such as side slip angle, yaw rate, current covariance, and current frequency and evaluate the operation safety of the vehicle. Finally, the current covariance and power spectrum are used to propose a comprehensive evaluation index to evaluate the operation safety of each IWM in real-time, and the effectiveness of the proposed method is verified based on the operation information of IWM-DEV.