R ed flour beetle (Tribolium castaneum) (Herbst) (Coleoptera: Tenebrionidae) is the major and a worldwide distribution insect pest in store grain that causes quantitative and qualitative damages to flour by feeding. T. castaneum is the most widespread pest in flour mills, warehouses and grocery stores (Garcia et al., 2005; Padin et al., 2002). Losses of grain estimated that post-harvest grain losses exceed $500 million annually and most of the losses are results of organism source such as insects or mycotoxin (Harein Abstract | Red flour beetle, Tribolium castaneum (Herbst) is a key insect pest of stored grain. Using radiation is an established method for controlling insect pests in store-grain and a significant stress factor affecting stored grain pests. The Present research work was designed to control T. castaneum through ultraviolet radiation (UV-B 313 nm) light is applied at various timings such as 0, 5, 10, 20, 40 and 60 minutes UV-B light on all developmental stages of T. castaneum. The results revealed that significant mortality was observed in eggs, larvae and pupal stage at all given timings of UV-B light compared with control. Incubation period of eggs, developmental period of larvae and pupae gradually increased as increasing exposure time of UV-B light. Statistically, no significant difference was observed between 5 minutes UV-light and control group on the incubation period of eggs and larval stages. Significantly, adult longevity of T. castaneum was reduced at all given timings of UV-B light as compared to control. However, a significant weight reduction was noticed on larvae, pupae and adult stages from 20, 40 and 60 minutes UV-B light as compared to control. Whereas no statistical difference was observed using 5 and 10 minutes UV-B light as compared with control. Use of UV-B light is a helpful technique for the management of T. castaneum because we found that all developmental stages of T. castaneum showed susceptibility on UV-B light that may be useful for the protection of stored grain products from T. castaneum infestation.