The main objective of this thesis is to detection of brain tumor with the results provided by image processing of the patient's MRI image.The brain tumor is a highly aggressive disease, which is difficult to resects totally. The surgical extent of resection constitutes a key role due to its direct influence on the patient's survival time. For detecting grayscale accurately Magnetic resonance imaging (MRI) is a common approach. the key objective of this thesis is to form a methodology to detect & extraction of brain tumor from patient's MRI scan images of the brain. This method incorporates with some noise removal functions, segmentation and morphological operations which are the basic concepts of image processing.Our proposed method will take input from MRI image. Input image will convert to gray scale image, then it will be adjusted based on the maximum intensity level, for avoiding excess data.