The interferenee phenomenon of two point light sourees is an important fundamental content of waveoptics.A simulation program was designed based on the Python software for displaying the interferencephenomenon of two point light sources in the global space. The light sources andobservation screen areeonstructed in the three-dimensional space coordinates.'The interference intensity in the observation sereen iscaleulated aeeording to the optical path dilferenee of the two point light sources reaching each point of thescreen,The coordinates of each points were transformed by a rotation matrix, so that the interference fringes inthe global space can be obtained.The results show that, various parameters can be adjust conveniently in thesimulation program, and the interference fringe patterns in the global space can continuously display , which isbeneficial to helping students understand the prineiple of light interferenee.