A new minimum-discontinuity unwrapping algorithm based on edge detection is proposed to overcome the disadvantage of Flynn′s minimum-discontinuity approach and unwrap the wrapped phase images rapidly and efficiently. In the new algorithm, isolated noisy pixels are excluded from the scanning areas of searching for improving loops firstly, and then the phase′s discontinuous areas within wrapped phase image are detected based on edge detection techniques and taken as the scanning areas. Because the required scanning range is cut down to a large extent by use of edge detection methods, the efficiency of the minimum-discontinuity phase unwrapping algorithm is significantly improved. The principle and implementation steps of the new algorithm are described in detail, and some computer simulation and experimental wrapped phase images are used to verify the effectiveness of the algorithm. Unwrapped results show that the proposed algorithm works perfectly and is more effective than the Flynn′s minimum discontinuity-approach.