Abstract: Using the Romax Designer engineering analysis software and the ISO/TS 16281 life calculation method, based on the classic rolling bearing theory, a large amount of calculations were conducted on the internal load distribution, contact stress, equivalent dynamic load of the ring raceway, and ISO/TS 16281 life of the motor shaft deep groove ball bearing for a fan under different radial clearances. The focus was on a detailed analysis of the fatigue life of the bearing and the effect of radial clearance on the lifespan of bearing ISO/TS 16281 was analyzed. The research results indicate that the influence of radial clearance on life is not only through the influence of internal load distribution, contact stress, and equivalent dynamic load of the ring raceway of the bearing, but also through the influence of factors such as life correction coefficient and there exists a relatively optimal radial clearance under the same operating conditions. Due to the different loads on the two bearings of the studied motor, the relatively optimal radial clearances are different. The research results can provide reference for the optimization design of deep groove ball bearings.