Abstract: It has long been known that frequent oral exposure to insect- infested flour run an increased risk of many diseases, including cancer, kidney failure etc in experimental animals. The susceptibility to all of these diseases may be a consequence of superimposed oxidative stress due to lack of defensive mechanisms. In concern with this hypothesis, the present study was carried out to assess the influence of feeding insect-infested wheat flour on the oxidant and antioxidant status in rats. Wheat flour samples were infested with Tribolium confusum for eight weeks then introduced immediately in feeding the rats for ten weeks. During the feeding period, blood samples were drawl for hematological studies periodically after each two weeks. The obtained data revealed that activities of antioxidant enzymes GSH-Px and GSH-R were found lower in the erythrocytes of rats feeding insect-infest wheat flour. By ten weeks of feeding the infested flour, the lowering ratios in these enzyme activities were 9.27 and 32.09% respectively. The GSH/GSSG ratio in plasma, which provide a sensitive index of whole body oxidative stress, were lower significantly and recorded 5.29 ±1.35. Plasma levels of antioxidant vitamin (vitamins A, C and E) were also significantly lower in plasma of rats feeding insect-infested wheat flour for ten weeks of feeding the infested flour and the lowering ratios for these vitamins level were 38.25, 37.49 and 43.21%, respectively. Additionally, levels of oxidants in plasma, TBARS, nitrite (NO2) and nitrate (NO3), were higher by the ratio of 124.92, 188.97 and 178.35%, respectively. Results suggested that enzymatic antioxidant defence system of erythrocytes was depressed and the erythrocytes were exposed to oxidant stress due to insect-infested flour feeding. Increased plasma TBARS, NO2 and NO3 levels indicated that not only erythrocytes but also some other tissues and cells might be exposed to the radical stress by insect-infested flour. Feeding insect-infested flour also caused significant changes in the levels of antioxidant vitamins partly protected erythrocytes against such harmful effects of feeding on infested flour by scavenging free radical species and by activating or inducing antioxidant enzymes.