Abstract: According to the space gear meshing theory, the mathematical modeling of the gear hobbing process with new structure of the micro hob, which has only one start and the teeth on which are arranged in staggered type, has been established. The forming process of the un-deformed chip and the instantaneous gear gap has been simulated with the aid of Boolean operation function in the CAD environment. Further, the instantaneous gear gap produced in the CAD environment is guided in the DEFORM-3D environment so that the formation and flow mechanism of the chip together with the stress analysis of the typical cutter tooth have been implemented. In this way, the distribution figures of the equivalent stress of the cutter tooth and the gear gap could be obtained at each instantaneous time.