Objective By a thorough analysis of the baseball batting to provide a theoretical instruction for baseball players with a simple and efficient dynamic model. Method Based on the moment of impulse theory, the closed form linear equations were derived by the dynamic analysis of the hinged multi-rigid body model. The numerical results would be obtained after solving the equations. Results (1) The batting speeds have been obtained by the numerical calculation under various conditions of different initial speeds of the baseball and bat; (2) The knockout speeds of wood bats are much smaller than the aluminum ones; (3) The coefficient of restitution has the significant effect on the batting speeds, and has no effects on sweet spot and center of position. Conclusions The numerical results are consistent with the data of experiments in reference. The calculating procedure is easy for baseball coaches and players to understand and can be applied in the training of baseball batting directly.