Abstract: Based on analyzing the phase and electric field characteristics of different combination of reflective mirrors in semiconductor lasers,the corresponding standing-wave patterns were studied carefully.The results show that the standing-wave pattern is closely related with the choice of the index of the top reflective mirror,and the overlapping position of the center of the active layer and the standing-wave greatly effects the confinement factor and the threshold characteristics of vertical-cavity surface-emitting lasers(VCSEL).