Particles will be crushed with the changes of the particle size distribution and the mechanical properties when they are subjected to impact load. With the increase of the degree of particle crushing, the final particle distribution will tend to self-similar distribution, which is called fractal distribution. The tests were carried out for clinker and marble particles in order to study the effect of impact load on particle size distribution, the PSD curves and the variation law of fractal dimension of the two kinds of particles are obtained when they are subjected to impact load. The results show that particles will not be crushed without limitation, the PSD curves consistent with the fractal model, the fractal dimensions increase with the degree of particles crushed which exist a limit value. The expression of energy dissipation and the strain energy of particle crushing are derived by contacting the final fractal dimension and mechanical properties. According to the theory of fracture mechanics, the energy balance equation of particle crushing can be well described by the law of energy conversion in the process by ignoring the friction between particles.