Backgrounds and Objectives: Providing safe drinking water is one of the main purposes in the community and achieving development and improvement of community is related to the public health. It is clear that people health depends on desirable drinking water supply. The objectives of this study are determining microbial quality of drinking water in Ardabil’s villages and determination of safe water usage of rural population in terms of microbial quality in the months of October and November 1389. Methods: In this cross-sectional study microbial water quality in 30 villages of Ardabil was measured in 2 times based on 3 criteria, i.e. Total Coliform (TC), Fecal Coliform (FC), and residual free chlorine. Results: Results show that residual free chlorine concentrations in 26.66and 33.33% of rural population drinking water were in a range of 0.2-0.8 mg/l in the months October and November, respectively. Total Coliform levels in 99.66% of the sample tested in October and 100% of them in November were negative. Average indicator in Desirability level for lack of heat-resistant E. coli test in surveyed areas in October was 96.66% and in November was 100%. Also pH levels in these months ranged from 7 to 7.8. Conclusion: According to 2006 guidelines of WHO on evaluation of microbial safety of drinking water, the average desirability indicator for lack of E. coli in studied areas were 96.66% in October and 100% in November, both being in excellent range.