Abstract: Based on the assumptions that the tube-rod extended penetrator materials can meet the rigid-plastic constitutive relations and a penetrator can be seen as quasi-steady movement in a penetration process, a simplified model for the telescopic penetrator of the normal penetration into a semi-infinite target is presented, through the respective theoretical analysis on the penetration stages of the head, the tube, the overlapped part of the tube and rod, and the rod. Tested experiments and numerical simulations on the extended penetrator were carried out at the speed between 1300 m/s to 1500 m/s. The comparison between theoretical results and the experimental as well as emulational results show that the simplified model and the simulation being adopted have good reliability. The morphology characteristics and the formation mechanism of the crater in the process of a normal penetration into a target, and the comparative advantage of this structure in a penetration and the law of change of the penetration depth increasing with speed are concluded.