Coherent beam combination technology is a significant approach for achieving high power laser beam with good beam quality. Based on“mutual injection and evanescent wave” characteristics of corner-cube resonator, it reveals that far field output of corner-cube laser was the inner reason and mechanism of coherent combining distribution by theory of evanescent wave. Evanescent wave coupling phase-locked combining characteristic in solid state laser was studied emphatically. The results indicate that the phase locking output is influenced by the distribution of laser beams and some other factors. When the distribution of laser beams is same, the cavity length and duty ratio determine the phase locking result. The longer cavity length and larger duty ratio, the stronger evanescent wave coupling is, so the phase locking result is much better, running to an in-phase mode output. Theories and experiments indicate that corner cube is a natural coherent combination element, and coherent beam combination technology by corner cube has important scientific value.