Based on the verified numerical model, impact responses of metal mesh enhanced shielding layer against high-speed projectile penetration were studied parametrically from aspects of projectile penetration depth, crater diameter, local damage situation and energy variation. The involved parameters included layout of metal mesh, diameter of metal wire, aperture of metal mesh and number of metal mesh layers. The study results showed that adding metal mesh into plain concrete shielding layer can effectively reduce projectile’s penetration depth, its residual velocity and crater diameter, improve local damage situation, and speed up projectile’s initial kinetic energy dissipation; appropriately increasing mesh density per unit area or volume fraction of metal mesh can further improve the anti-penetration performance of metal mesh enhanced shielding layer, the specific measures include spiral arrangement of metal mesh, increasing diameter of metal wire, reducing aperture of metal mesh and increasing number of metal mesh layers, etc. Finally, based on the numerical study results, a calculation formula was proposed to predict projectile penetration depth into metal mesh enhanced shielding layers arranged in parallel. It was shown that the formula has higher fitting accuracy; it can provide a useful reference for the specific application of the shielding layer in protective engineering.