Edge detection is an important field in image processing. It can be used in many applications such as feature detection and extraction. An edge is detected as the discontinuity in intensity level of a point. So edges are mostly detected using either the first derivatives, called gradient, or the second derivatives, called Laplacien. In this paper, we propose a new edge detector using the gradient of gamma distribution. The results were very good compared with the well-known Sobel gradient and Canny gradient results.