Iintroduction: Because of entering organic material and mud, lakes and reservoirs are naturally subject to change. Entrance of macro nutrients (nitrogen and phosphorus), inorganic and organic material into reservoirs and lakes, leading to the changes in the quality of water. Therefore, this study aimed to determine the parameters of water quality assessment was conducted in 2012 in Chahnimeh of Zabol.Methods: In this cross sectional study that was performed for eight months, from early April to October 2012, on water reservoir of number 3 Chahnimeh of Zabol city. At present study every 15 days, samples were collected from the bottom of the reservoir using Nansen bottle and then temperature, turbidity, dissolved oxygen, heavy metals, phosphorus and coli form bacteria levels were measured in the laboratory according to standard procedures. Also, SDT parameter was measured by secci disk. Data analyzed by SPSS software using descriptive and analytical statistics by one sample t test, and p£0.05 was considered as significant.Results: The mean concentrations of nitrate, phosphate, COD and dissolved oxygen concentration were 11.17, 0.02, 21.13 and 8.7 mg/L, respectively. Average total dissolved solids, sulfate, nitrate and total hardness, were 450.43, 138.41, 11.17, 199.40 mg /l, respectively. Average total of coli form and E.coli bacteria were 27.5 and 1.1, and a significant relationship were observed between water chemistry values for all parameters (p£0.05).Conclusion: According to the results, all parameters were within the standard of compliance for drinking. The estimation of reservoir water showed water quality management plan for the protected Chahnimeh NO: 3 requires further.