Using Matlab software, the Lissajous diagrams of two simple harmonic vibrations with differentfrequencies perpendicular to each other are simulated under four conditions;one cycle process ,the same initiaphase but different initial phase difference , different initial phase but same initial phase difference , and thesame initial phase difference in one cycle.From the simulation diagram,the motion track process of Lissajousdiagram can be seen.The Lissajous diagram is related to the initial phase and initial phase diference of the twosignals,and the initial phase difference changes periodically with time, the synthetic Lissajous map alsoundergoes periodic changes.