The type selection analysis of an axle box bearing for the gauge-changeable bogie of high-speed EMUs was described, including the analysis of bearing form, bearing precision, bearing material, lubricating grease type, grease filling amount, bearing seal and bearing clearance, etc., and the basic type and size of the bearing of the gauge-changeable bogie were determined. Considering the application characteristics of the gauge-changeable bogie, according to the safety guidance, with the stress calculation of the tapered bearing on the partial load side being 1.6 times that of the stress calculation without deflection, when the equivalent load was 21.75 mm, the calculation mileage of the bearing could still reach 1 million 900 thousand km. The calculation results showed that the selected bearings met the design requirements.