The introduction of novel applications in X-ray breast imaging warrants new research for image acquisition optimisation. A simulation model was developed to investigate the influence of different imaging techniques and acquisition parameters. It was modelled in Monte Carlo N-Particle Extended and contains an X-ray tube with photon production, a breast model and antiscatter grid model. This paper describes the simulation model, compares the results with experimental and literature data and presents the influence of breast and antiscatter grid parameters on scatter radiation.