The ballistic properties of different thickness combinations of ceramic/UHMWPE composite armors were studied in this paper, in order to find a better ballistic property structure subject to 12.7mm bullet. Powder-gun ballistic testing system was used to carry out the normal impact tests to determine the response and the ballistic limit of these combinations of ceramic/UHMWPE composite armors subject to impact loading. Compared with the test, an explicit finite element (FE) model was built with LS-DYNA Code to simulate the impact process. The influence of different parameters on the impact behavior was considered analytically. Results show very good agreement with the experimental data.