Disclosed are human tissue phantoms mimicking the mechanical properties of real tissue, and methods for manufacturing thereof including the steps of obtaining a computer aided three-dimensional design of a phantom mimicking the tissue in shape and size; fabrication of a mold form facilitating the production of the designed phantom; molding said phantom with the use of two-component silicon gels as a bulk tissue-mimicking material having Young's modulus in the range of 2 to 30 kPa; filling the enclosed volume of said phantom with anatomical and pathological tissue structures mimicking their respective mechanical properties and having Young's modulus in the range of about 30 to 600 kPa; covering said phantom by a protective layer having mechanical properties to a human tissue protective layer; and securing the phantom perimeter on a supporting plate by a rubber barrier. The example of used tissue-mimicking material is a two-component silicone SEMICOSIL gel with variable elastic properties and Young's modulus from 3 kPa to 600 kPa as a result of changing the silicon component ratio. As examples, the breast and prostate phantom tissue and their fabrication procedures are described.