The invention relates to a motion detection method based on edge detection and frame difference. The method comprises the following steps of: 1, acquiring an image sequence and determining images of a reference frame and a current frame; 2, performing Gaussian filtering on the images of the reference frame and the current frame; 3, extracting the edge information of the reference frame and the current frame after the filtering; 4, acquiring converted images of the reference frame and the current frame; 5, performing the frame difference on the converted images of the reference frame and the current frame, and determining a motion region by using a double threshold value method; and 6, performing image post-processing on the motion region, and determining a motion object. The method has the advantages that: due to the adoption of the thinking of frame difference, the method is simple and practical, the complex computations of an optical flow method and hybrid Gaussian are avoided, computing time is only 1/3 of that of classical hybrid Gaussian, and requirements on the real-time performance of intelligent monitoring are met; incomplete frame difference detection results are improvedto a certain extent by the combination of the edge detection and the frame difference and a series of additional processing; and compared with the hybrid Gaussian serving as a mainstream method, the method is difficult to influence by illumination and external interference.