The red flour beetle (Tribolium castaneum) pest infestation could be a terrible major problem as various life stages of insects cause economic damage and deteriorate the standard of food grains—the insect T. castaneum and its body parts were dissected and measured were recorded based on calibration readings. In sesame seeds maintained, an experimental setup has roasted and unroasted viz BOD incubator, refrigerator, water spray, sundry and regular room temperature applied sesame seed to prevent T. castaneum pest infestation at 15 days interval for analyzing the germination test and germination index. Infected dead T. castaneum pests were collected, and fungi were isolated by culture plate technique with frequency percentage. The T. castaneum faecal matter was tested in a field emission scanning electron microscope (FESEM). A result indicates that the measurements and the complete life stages of T. castaneum were recorded. Rhizopus stolonifer, Rhizomucor fungus culture were identified from the roasted and unroasted water spray treatment. Aspergillus (57.1%), Penicillium (14.2%), Acremonium (14.2%), Mucor (14.2%) were the most dominant fungi among those isolated from infected red flour beetle of sesame seed samples. FESEM analysis in the excreta of T. castaneum toxic or adverse health effects.