The aim of this work is the evaluation of the software BreastSimulator, a breast X-ray imaging simulation software as a tool for the creation of 3D uncompressed breast digital models and for the simulation and the optimization of computed tomographic (CT) scanners dedicated to the breast. Eight 3D digital breast phantoms were created with glandular fraction in the range 10% to 68%. The models are characterised by different sizes and modelled realistic anatomical features.. X-ray CT projections were simulated for a dedicated cone-beam CT scanner and reconstructed with the FDK algorithm. X-ray projection images were simulated for 5 mono-energetic (27, 32, 35, 43 and 51 keV) and 3 poly-energetic X-ray spectra typically employed in current CT scanners dedicated to the breast (49, 60, or 80 kVp). Clinical BCT images acquired from two different clinical breast CT scanners were used for comparison purposes. The quantitative evaluation included calculation of the power-law exponent, β, from simulated and real breast tomograms, based on the Noise Power Spectrum (NPS) fitted with a function S(f) = α/fβ. The breast models were validated by comparison against clinical breast CT and published data. The calculated β coefficients are close to that of clinical CT data from a dedicated breast CT scanner and reported data in the literature.In this paper we evaluated the software package BreastSimulator to generate breast models suitable for use with breast CT imaging The breast phantoms produced with the software tool can reproduce the anatomical structure of real breasts, as evaluated by calculating the β exponent from the power spectral analysis of simulated images. As such, this research tool will contribute considerably to the further development, testing and optimisation of breast CT imaging technique.