Malignant neoplasms are one of the principal world health concerns and breast cancer is the most common type of cancer in women. Advances in cancer detection technologies allow treating it in early stages; however, it is necessary to develop treatments which carry fewer complications and aesthetic repercussions. This work presents a feasibility study for the use of microwave ablation as a novel technique for breast cancer treatment. A microwave applicator design is also being proposed for this purpose. The coupling of the designed antenna was predicted with computer simulation. The standing wave ratio obtained through simulation was 1.87 and the result of experimental validation was 1.04. The optimized antenna has an optimal coupling (SWR = 1.04) so ablation temperatures can be achieved in a relatively short time using low power. Varying the time and power, the heating pattern can be changed to treat different tumors. However, as some discrepancies are still present, a deeper study of the dielectric properties and their variation with temperature is required.