This study objective is to evaluate the simulation results of the 3DCRT technique TPS in breast cancer cases to conform to the standards permitted by the International Commission on Radiation Units and Measurements (ICRU). The TPS process uses the Eclipse program with the Anisotropic Analytical Algorithm algorithm. The 3DCRT cumulative dose-volume histogram curve was analyzed to obtain the absorbed dose received by the organ at risk (OAR) of the left lung, right lung and heart. The TPS results show that the dose received by OAR was below the prescribed threshold of the left lung with a mean dose of 54.7 cGy covering a volume of 1238.5 cm3 and to the right lung the mean dose of 2113.2 cGy surrounding the volume of 1474, 5 cm3 and at the heart the mean dose of 96.5 cGy covers a volume of 175.5 cm 3. TPS simulation carried out successfully obtained data on the planning of radiation from breast cancer cases that met the relative dosage requirements that covered the volume of PTV permitted by ICRU (95% -107% enclosed volume), that is, the relative dose for the target of 95% which covered 95.5% of the target volume.