Cancer is one of the vital causes of death worldwide. Chemotherapy, immunotherapy, radiotherapy, surgery or combination of these are among the most popular cancer treatments. To hinder tumor growth and have a better result in treatment, combination of chemotherapy and radiotherapy have been commonly in use. Sometimes the high efficiency of this approach make surgery unnecessary. In recent years, the use of mathematical modelling to predict the effect of treatment, survival time, and to optimize the treatment has been important and widely used. Moreover, all part of the tumor is not visible in MRI(T1Gd), due to having a threshold of detection often higher than most part of the tumor, so by the use of mathematical modelling, all part of the tumor are visible. In this project, an accurate geometry of the brain was modelled using cloud points, and different areas of the tumor including white matter, grey matter, and ventricles were distinguished and were entered into the COMSOL. The growth of tumor, chemotherapy and radiotherapy were modeled, using partial differential equations. Schedules relating to each treatment were added to the equations. Different types of radiotherapy including hyperfractionated and conventional, chemotherapy using temozolomide, and their schedules, radiosensitivity parameter, the visible area in MRI(T1Gd) and the survival time are among the goals of this project. The survival time of the first patient at the lowest and highest radiotherapy sensitivity increased by 1 month and more than 2 months, respectively. The survival time of the second patient for whom preoperative surgery was modeled was increased by 2 months and more than 3 months at the lowest and highest sensitivity of radiation therapy, respectively. Hyperfractionated method showed a better effect in reducing the maximum concentration of cancerous cells and area of the tumor than the conventional method. Concurrent chemotherapy and radiation therapy showed much better performance in preventing growth and reducing the area of the tumor than the Sequential chemo-radio therapy, as the patient will live 40 days longer. Keywords: Tumor-Cancer-Combining chemotherapy and radiotherapy-Temozolomide-MRI(T1Gd)