Abstract: The failure behavior of 35CrMnSi steel projectile during the high velocity impacting was investigated in this paper. The 35CrMnSi steel was treated with oil and water double-quenching and low temperature tempering, its static tensile strength and dynamic compressive mechanical properties were tested, and the metallographic was also analyzed. Using 35CrMnSi steel projectile to impact the low carbon steel plate, the failure characteristics at different velocities were got in the experiment; using scanning electronic microscopy (SEM) to inspect the microstructure of the fracture area, the failure behavior of the cylinder 35CrMnSi steel projectile at different velocities was analyzed. In accordance with the one-dimensional impact theory analysis, the fracture failure behavior threshold condition of 35CrMnSi steel projectile was finally got; it could be used as reference for relative researches.