Abstract: Based on the class fuzzy C-means clustering algorithm (FCMA) is a well-known clustering method to partition an image into homogeneous region.We know FCMA is dependent on the choice of the initial distribution of cluster center, and consequently the algorithm ends up in a local optimum. Because of the genetic algorithm which can achieve the global optimum, we directly unified them in the magnetic resonance images (MRI) segmentation. By applying genetic algorithm, we can achieve the global optimum in MRI segmentation application.