In order to stitch the sub-aperture data rapidly and precisely in microsphere profile inspection, the model of microsphere surface measurement was given, which was based on point diffraction interference. After analyzing the distribution of interference field lateral resolution in detail, a method of sub-aperture stitching based on mapping image matching was proposed. After equal-scale transformation of profile data, the homogenization of lateral resolution was achieved. The dimension of 3D point clouds data was reduced to a mapped 2D image for transforming the sub-aperture rotation-ship of the profile data to a translation relation on the CCD coordinate system. And the corresponding transformation offset between sub-apertures could be obtained by the feature points matching in ways of image matching algorithm, so the sub-aperture stitching could be realized. Finally, the feasibility and effectiveness of the proposed mapping image matching method for sub-aperture stitching was proved by the simulation experiment.