Breast mass segmentation in mammography plays a crucial role in Computer-Aided Diagnosis (CAD) systems. We propose in this article a method for the segmentation of mammography images. We use a combined solution of the two approaches; one based on levels set theory and the other based on the principle of the minimization of the energy of active contours. The elaborated algorithm which is an interactive approach permits to segment effectively the images from its coarse resolution to its refinement. The results of the segmentation are illustrated from the database of MIAS.