Existing wireless control laser pointer with the function of paging PPT in projector can control the move of the mouse pointer. The original problem is that the traditional wireless mouse is unhandy with the mouse pointer moving in frames. To address the difficulty, this project through the camera getting images on the projection screen can first determine the edge of the screen, using frame difference algorithm to extract feature points of the laser light, then call the API of windows and finally move the cursor to the appropriate specified place. Four image processing modules are designed in order to accomplish the process. The result turns out that the mouse can move freely according to the laser spot. Experimental results show that light intensity of the external environment does not affect the control. Moreover, under the normal indoor environment, mouse delay and maximum use of the distance meet the practical requirements.