Abstract: A strain of Tribolium castaneum (Herbst) was developed for resistance against deltamethrin, after six generation of selection from a laboratory susceptible strain, through topical application method. The selection was initiated at the dose 0.0004, which was increased during successive generations’ upto 0.026 in sixth generation. The resistance ratio of selected strain was determined, and it was found to be 370.5 fold in sixth generation as compared to susceptible strain.