The invention relates to a curve corner point detection method based on difference accumulated values and three-point chain code differences, which is technically characterized by comprising the following steps of: firstly carrying out Freeman chain code encoding to the obtained curve, calculating the difference accumulated values of the chain codes point by point according to the Freeman chain code encoding sequence based on the obtained Freeman chain codes, and dividing all pixel points on the curve into determining points, non-corner points and doubtful points through the difference accumulated values of the three-point chain codes; then calculating the three-point chain code differences of the doubtful points, and judging the doubtful points through the three-point chain code differences to find out true corner points in the doubtful points; and finally merging the corner points found in the determining points and the doubtful points to obtain all corner points of the curve. In the method, the points with curvatures to be calculated are judged by adopting the three-point chain code differences to replace the curvatures, thereby further reducing operation workload and lowering operation complexity. The corner points detected in the method also contain sequence characteristics which provide convenient for utilizing the corner points to carry out image processing.