This study ailm was to fabricate and investigate the gamma photon shielding efficiency of antimony (Sb) doped polymer resin composites. The orthophthalic unsaturated polyester resin (C 16 O 7 H 14 ) and antimony powder have been used as matrix and filler material, respectively. Gamma radiation shielding capacities of the polymer resin composites doped with 325 mesh sized-antimony particles from 5 to 20 wt% have been investigated. Experimental measurements of the samples have been obtained using an HPGe detector equipped with gamma spectrometer by 241 Am, 133 Ba, 57 Co, 22 Na, 137 Cs, 152 Eu, 54 Mn and 60 Co radioactive point sources varying from 59.5 to 1408.0 keV energies. To explore the gamma-ray attenuation features, linear attenuation coefficient (LAC), mass attenuation coefficient (MAC), half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff), the radiation protection efficiency (RPE) were evaluated. According to the obtained results, it was found that Sb(20%) showed the superior radiation shielding capacity than the other samples. The measured data have been compared with those of WinXCOM, and they were found to be in a good agreement with each other.