Polyacrylic acid （PAA） lead was successfully prepared as radiation-protection materials via graft copolymerization route. The product was characterized and analyzed with Fourier transform infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）. Gamma energy-spectrum measurement was carried out to evaluate its radiation-shielding properties. EGSnrc user code was also employed to theoretically simulate its above properties based on Monte Carlo method and analyze the influences of this material on the fluence and dose in the detecting area. The results revealed that this composite material has excellent radiation-shielding ability and this ability decreased with the increase of γ-ray energy. According to our theoretical simulation, in pure air, the change of fluence is discontinnous and looks like a ladder whose step width beomes narrower grdually and the dose increased slowly whith depth. When the sample was put into the air, in the air medium area, the changes of fluence and dose were no longer related with ray energy but with the sample thickness, while in the sample medium area, the changes of fluence and dose were not rectilinear and the rate of changes makes an obviously turn at the boundary between the sample and air.