The authors' aim is to provide breast surgeons' perspectives on the relative importance of the criteria for choosing an appropriate surgery method between mastectomy (total removal of a breast) and breast-conserving surgery (removal of a breast cancer tumor and some of the normal tissue that surrounds it) for women with breast cancer by using the multicriteria decision-making method (MCDM). The Analytic Hierarchy Process (AHP), the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), and Vise Kriterijumska Optimizacija I Kompromisno Resenje (VIKOR) methods are utilized. A decision hierarchy is set with a goal, criteria, and alternatives. We developed our model based on three main criteria, tumor-related, patient-related, and post-operative process-related factors and nineteen sub-criteria, as well as two alternatives, mastectomy and breast-conserving surgery (BCS). An online questionnaire was sent to the breast surgeons; we showed that the most important criteria are post-operative process-related factors, especially the demand for esthetic appearance based on 39 breast surgeons. Conversely, the least significant criteria are tumor-related factors. Furthermore, breast-conserving surgery is selected as the most appropriate surgery method for breast cancer patients using the AHP, TOPSIS, and VIKOR.