This paper presents the results of mathematical simulation carried out to confirm the ability of holographic radar to detect breast tumors. The simulation software used the Finite- Difference Time-Domain Method. The simulations were performed for three different scenarios: in the first model the inclusion depth under the surface was varied; for the second model two inclusions were used; while the dielectric properties of malignant tissue were modified in the third model. The model is a 3D block with dimensions 200 × 200 × 100 mm, which mimicked normal breast tissue, with one or two spherical inclusion — malignant neoplasm of breast tissue. Frequency dispersion of normal and malignant tissues dielectric properties (conductivity and permittivity) was taken into account. The results showed that differences in the dielectric properties allow to use of the radiolocation method for detecting inclusion (diameter 4 mm) on a depth up to 5 mm. The results proved that the greatest impact on the detection of inclusion has a ratio of conductivity values of normal and malignant tissues. Also the proposed method makes possible to distinguish two different objects at the distance between them of 16 mm or more, otherwise they will be identified as one inclusion.