Abstract: Based on depth of penetration experiments, anti-penetration experiments were conducted in constrained AD95 ceramic targets and 10%-zirconia-toughened alumina ceramic targets subjected to shaped charge jet penetration.The depth of penetration-time curves for these two types of ceramic targets and their residual penetration depths in validating targets were obtained, and these data were compared with the corresponding experimental data for 45 steel targets.Results show that the protection coefficients of these two types of ceramic targets are both bigger than 1.0, that the anti-penetration abilities of the constrained ceramic targets are improved distinctly, and that the anti-penetration abilities of the toughened ceramic targets are larger than those of the AD95 ceramic targets.Based on the experimental results, the anti-penetration mechanism of the constrained ceramic targets to shaped charge jets was analyzed, and the following conclusion is presented: the disturbance of back-explosion generated from the constrained boundary to the jet stability is the main cause why the constrained ceramics have better anti-penetration ability than the unconstrained ceramics.