Objective: to determine the effect of preoperative MRI on the treatment plan in women newly diagnosed with breast cancer. Subjects: the study included 40 patients newly diagnosed with breast cancer who did not have any type of treatment or underwent any type of operation. Methods: This prospective controlled study included 40 patients newly diagnosed with breast cancer who did not receive any type of treatment or underwent any type of operation the plan of the therapy was compared before and after MRI examination to document the impact of MRI on the plan of therapy. Results: Only 10 patients of the included cases had the therapeutic plan significantly changed after MRI examination while the other 30 patients had the same therapeutic plan pre and post MRI examination. Conclusion: Breast MRI proved to be the best imaging modality for pre-operative evaluation of breast cancer for proper determination of the therapeutic plan in patients newly diagnosed with breast cancer.