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Introduction: Nitrate and nitrite are considered as ground water pollutants in recent years due to the increasing the industrials, agricultures and as well as municipal wastewaters. The concentration of these pollutants in ground water is increasing. The aim of this study was to investigate the nitrate and nitrite concentration in Ilam Township. Materials and Methods: This descriptive-analytical study was carried out on 60 drinking water wells at the various location of Ilam. 60 water samples were collected and the content of nitrate and nitrite of the samples was determined with spectrophotometer (DR-5000). The data was finally analyzed by SPSS and Arc view GIS softwares. Findings: The findings showed that the concentration of nitrate and nitrite in 98.33% of the samples was lower than the standards and 1.67% of the samples had the ions concentration higher than the standards. The highest concentration of nitrate ions (10.5 mg/l on the basis of N) was attributed to the well studied at Haft Cheshmeh Village located in the agricultural area. The highest concentration of nitrite ions (1.19 mg/l on the basis of N) was also belonged to the well studied at Abza Village located in the agricultural area. There was no significant difference between the concentration of nitrate (p-value=0.96) and nitrite (p-value=0.71) among the various area (agricultural, industrial and urban). Discussion & Conclusion: It was concluded that the water quality studied was now corresponded to the Iran drinking water standards. Nevertheless, the monitoring of these water resources is essential and treatment and sanitary disposal of wastewaters most be considered. Keywords: Ilam, Ground Water, Water Pollution, Nitrate, Nitrite.