Non aqueous reactive polymer materials produced by the reaction of isocyanate and polyol have been widely used in infrastructure construction, which may be subjected to explosion loads during complex service conditions. The blast response of composite materials is a crucial aspect for applications in engineering structures potentially subjected to extreme loadings. In this work, damage caused to rebar reinforced polymer slabs by surface explosive charges was studied experimentally and numerically. A total of 6 field tests were carried out to investigate the performances of the failure modes of rebar reinforced polymer slabs under contact and near-field explosions. The influence of explosive quantity (10–40 g) and stand-off distances (0–20 cm) at the damage modes were studied. The results show that the failure modes of rebar reinforced polymer slabs under near-field explosion mainly were bending and surface spalling, while under the impact of contact explosion, the failure modes were craters of the top surface, spalling of the bottom surface, and middle perforation. Furthermore, a detailed fully coupled model was developed and validated with the test data. The influences of explosive quantity and slab thickness on rebar reinforced polymer slabs under contact explosion were studied. Based on this, the calculation formula between breach diameter, explosive quantity, and slab thickness is fitted.