Background: Providing Safe drinking water is a prime concerninany community. This analytical study was carried out to evaluate the microbial quality of drinking water in rural areas of northeastern Iran. Methods: The water microbial quality was determined in all villages (a population of 53047 people), in 3 rounds and based on 3 measurements, i.e. Total Coliform, Fecal Coliform, and Heterotrophic Plate Count. Census method was used for studying water distribution system too. Results: Results of heterotrophic plate counts of over 500 were positive in 19 (19.8%) of the villages.Total coliforms were also detected in 37 (38.5%) of the villages. Water in villages receiving the services of Water and Wastewater Company had significantly lower levels of total and fecal coliforms contamination (p<0.05) compared to villages deprived of these services. In 4.3% of the villages where the Company delivered services, the HPC≥ 500 results were positive, while this percentage rose to 24.7% in other villages ( p = 0.03). Conclusion: Comparison of the results of this study with guidelines published by WHO, regarding the microbial quality of water in 2006, indicated that the the microbial quality of the drinking water in rural areas in Maraveh Tappeh is desirable but lower than the Iranian standard.