Inspite of its non-inclusion in the prescribed list of food colors, orange II is extensively employed to color a variety of foodstuffs. Oral LD50 value of orange II in both male and female rats was calculated to be more than 10.56 g/kg body weight. In short-term studies, animals were exposed to diets containing 0.0 (control), 0.1, 0.5 or 3.0% (w/w) of orange II, daily for 90 days. Hematological examination revealed a slight decrease in erythrocyte count and hemoglobin content, whereas leucocyte count, PCV, ESR, MCV, MCH and MCHC showed normal values. There was no change in the activities of LDH, GOT, GPT, alkaline/acid phosphatases and bioconstituents, lactic acid, cholesterol and protein in serum as well as in liver, indicating normal functioning of the liver. Histopathological examination of various body organs such as liver, heart, lung, kidney, testes, adrenal, stomach, large and small intestine presented normal appearance. Animals receiving 3.0% orange II showed marked splenomegaly and deposition of Perl's positive iron pigments. Testicular LDH, hyaluronidase and lactic acid did not reveal any deviation from controls, suggesting normal spermatogenic process. No changes in testicular cholesterol, fructose content of coagulating glands and dorso-lateral prostate, and activities of alkaline phosphatase in seminal vesicle and acid phosphatase in ventral prostate support normal androgenic status.