In order to solve the noise sensitive problem in the traditional Canny edge detection algorithm, based on the curvature estimation of curve, the edge curvature degree operator is constructed according to the noise edge characteristics which are large curvature and small curved space. The edge curvature degree operator is modified with the results of edge detection of the large scale Canny algorithm so that the operator can accurately characterize the distribution of the noise intensity in the two-dimensional space. On this basis, an edge detection algorithm based on edge curvature degree operator is proposed and the edge curvature degree operator can restrain the noise. The experimental results show that the algorithm cannot only suppress the noise effectively, but can also preserve the rich details edges and the slowly changing contour edges, and the detection results show the original structural features of the image.