Fitting capabilities of rectangular array and hexagonal array segmented micro deformable mirrors on the basis of micorelectromechanical system technology are analyzed in terms of the characteristics of the mirror shape. The distorted wavefront and micro deformable mirror model are established by ZEMAX, and the simulation analyse on the correction capability of these deformable mirrors are made. The results show that the correction capability of hexagonal array is better than that of rectangular array under the circumstance of the approximate number of sub-aperture.