Abstract: To study the penetration characteristics of non-circular penetrators, simulations and analyses of penetration into semi-infinite targets were done on penetrators whose cross-sections were circular, equilateral triangular, and square. Simulation results were verified with the previous experimental data. Simulations were done to study the penetration power of three kinds of penetrators with different cross section shapes and length-diameter ratios of 5, 10 and 15 and two kinds of penetrators with Regular pentagon and Hexagon cross-sections. Results show that non-circular penetrators with bigger length-diameter ratios and higher impacting velocity had good penetration power; the penetrator with an equilateral triangular cross section had the greatest power. A parameter to name the cross section shape factor was put forward. Based on the Alekseevskii-Tate model, an empirical formulae for the impact of non-circular penetrator on semi-infinite targets was built.