Chromium exists in a series of oxidation states with a valence from -2 to +6. Trivalent (Cr[III]) and hexavalent (Cr[VI]) compounds are the most biologically significant. After entering the body from an exogenous source, Cr(VI) is rapidly taken up by erythrocytes after absorption and reduced to Cr(III) inside the cell. We have studied the influence of potassium dichromate (K2Cr2O7) on blood GSH values in female rats. This study was carried out on 49 adult white Wistar adult female rats divided in 6 experimental groups and one control group. The rats were feed with 25ppm (LOAEL), 50ppm and 75ppm K2Cr2O7, ad libitum, in drinking water. The control group received tap water. Reduced glutathione (GSH) was measured quantitatively using a spectrophotometer method. This study reports that potassium dichromate exposure induces depletion of blood GSH because Cr(VI) can generate reactive oxygen species (ROS). It can provoke oxidative stress and toxicity.