Background: Nitrate (NO3-) is one of the inorganic anions produced from the oxidation of nitrogen. The organic or inorganicnitrogen may act as a carcinogen depending on the reduction of nitrate to nitrite and the subsequent reactions of nitrite with othermolecules, leading to the formation of N-nitroso compounds. Objectives: This study aimed to determine the effects of nitrate and Vitamin C on oxidative stress in the renal tissue of rats. Methods: This experimental study was conducted in Iran during the 2017-2018. The sample size was estimated to include 55 Wistarmale rats using Morgan’ s table and Cochran’ s formula. In total, 49 rats were selected and divided into seven groups of: (1) NO3 = 0mg/L (control), (2)NO3 = 10 mg/L, (3)NO3 = 45 mg/L, (4)NO3 = 200 mg/L, (5)NO3 = 10 mg/L + Vitamin C 20 mg/100 gBW(BodyWeight), (6) NO3 = 45 mg/L + Vitamin C 20 mg/100 g BW, and (7) NO3 = 200 mg/L + Vitamin C 20 mg/100 g BW. Blood samples were obtainedto determine blood urea nitrogen (BUN) and creatinine. An autopsy was performed on the renal tissue to evaluate oxidative stressindicators including malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). Results: In this research, the fourth group showed a significant increase in the level of creatinine (50. 14 2. 6, 43. 14 1. 21, P = 0. 01)and BUN (0. 72 0. 04, 0. 57 0. 11, P = 0. 003) compared to the control group. On the other hand, a significant increasewas observedin the level of MDA in the fourth group compared to the control group (P = 0. 01), whereas a significant reduction was found in thelevels of CAT (P = 0. 001), SOD (P = 0. 02), and GSH (P = 0. 02). In addition, the levels of creatinine and BUN significantly reduced in theseventh group compared to the fourth group (P < 0. 05). Furthermore, the use of Vitamin C resulted in a significant reduction inMDA and an increase in SOD, CAT, and GSH in the seventh group compared to the fourth group (P < 0. 05). Conclusions: According to the results of the study, nitrate in drinking water and the prescription of Vitamin C had no significanteffect in the presence of nitrate doses of 10 and 45 mg/L. However, a 200 mg/L dose of nitrate significantly affected BUN, serumcreatinine, and oxidative stress indicators, causing the kidney disease.