In this study, nitrate and nitrite levels of drinking water in city of Bitlis were investigated. A total of 164 water samples, collected from the tank and tap water in Spring and Autumn were used as material. Analysis performed through spectrometric techniques showed that all samples contained some levels of nitrate and nitrite. The average nitrate and nitrite levels were 5.68+/-0.31 and 1.32+/-0.09 mg L(-1), respectively. The effects of residential areas and season on the nitrate and nitrite levels were found to be statistically significant (p<0.05). Nitrate levels of tank and tap water were in accordance with recommended standards. However, 12 and 100% of tank water samples and 7.02 and 100% of tap water samples collected respectively in Spring and Autumn did not meet the national standards for nitrite levels. In addition, 3.58% of tap water collected in Autumn did not meet the international standards.