Principle, characteristics, composition, performance and technique parameter of structure design of JK11412 bearing examination machine were introduced. With the fault diagnosis technique of generalized resonance & resonance demodulation, and related techniques of numerical control machine such as semi-motor, bilge type of elastic tonghold, synchronous pulley, linear guide rail, ballscrew nut fitting, etc, the single locomotive bearing-examining machine was developed for locomotive bearing fault detect. Practice has proved that the machine has features of high degree of automation, simple operation and high accuracy, and provides important guarantee way for the bearing examination.