Joints can reflect and transmit stress waves, thus joints affect rock fracturing, and accordingly they could affect blasting efficiency. In this paper, numerical and experimental investigations have been implemented and the effect of joints on wave propagation and rock fracturing has been discussed. A dynamic numerical model of jointed rock mass has been established by using finite difference method. The simulation results show that as joints are parallel to wave propagation, the corresponding rock damage zones increase. Blasting experiments by using artificial joints have been carried out. Generally the experimental results agree with our numerical results.