The material removal rate (MRR) of micro-detonation of striking arc machining (MDSAM) is studied. The orthogonal experimental design and regression analysis method are employed to build the empirical model and the influencing laws of processing parameters on impact force are educed. Experimental results show that the material removal rate decreases with the increment of working distance and increases with the growth of working current, working gas pressure and pulse width. The exponential type empirical model with feature of simple and reliable consists with experiment results well. The research can offer an important reference for the predication and control of material removal rate in the process of micro-detonation machining of striking arc.