Thermal experimentation and electric properties measurements are presented, using tumor breast phantom and breast phantom built in our laboratory. Electric properties were measured to find similar characteristics between breast and tumor breast tissue and phantoms. For tumor breast phantom, we obtained a variation of 4.1216 for dielectric constant and 0.3798 S/m for electric conductivity. Breast phantom had a variation of 0.7065 for permittivity and electric conductivity had a variation of 0.0066 S/m. Microwave ablation therapy was applied on both phantoms for five minutes, with 10 watts of power. According to literature reports, tumor breast tissue presents higher temperature than breast tissue, but our results present breast phantom temperature higher than tumor tissue. It is necessary to find other materials for tumor breast phantom to get higher temperatures than breast phantom.