The red flour beetle, Tribolium castaneum, is an important pest in wheat and maize mills. The goal of this study to determine the level of risk via examining the survival rate, oviposition, and development phases of this pest. The shortest development durations were recorded when the larvae reared on the whole wheat flour followed by wheat flour without bran (22.8±0.31 and 24.7±0.32 days, respectively). The longest development durations were recorded when larvae reared on corn flour without bran followed by bran only (31.1±0.28 and 31.5±0.34 days, respectively). The highest larval survival rate was 95% when larvae reared on whole wheat flour, whereas the lowest one was 94% when larval reared on both of flour without bran and bran only. Meanwhile the lowest survival rates were 84% and 83% when larvae reared on corn flour without bran and bran only, respectively. The longest oviposition period was recorded on wheat flour without bran (280.5±5.70 days). The adult longevity was the longest on wheat flour without bran. The number of progeny produced by the first generation was higher on whole flour than flour without bran. The large differences between the various flour types suggest varying levels of risk by insect infestation. Understanding What insect diets successfully used is essential for creating management measures as customer interest in these alternative flours grows and they become more common in food facilities.