Microbial Safe drinking water supply has always been a main challenge for authorities in rural areas. The aim of this study was to investigate the microbial quality of drinking water distribution system in rural areas of Marivan city, Iran. The sampling was performed in a 12 months period from March 2010 to February 2011. Totally samples were collected during a 12 months period. At the site, 250 ml polypropylene bottle containing 0.4 ml of a 10% sodium thiosulfate solution was used for collecting water samples and transported to laboratory in 6 h and 4°C. In order to determine the quality of water, the turbidity, free residual chlorine, total and fecal coliform were analyzed. The result showed that the minimum and maximum of pH were 6.8 and 7.8 respectively. In 95% of samples residual chlorine was between 0 and 0.8 mg/L. The MPN of total coliforms was in the range of 0 to 1100/100 mL. The amount of fecal coliforms in 95% samples was lower than 23 MPN/100 mL. The maximum value of turbidity was 113 NTU. It is necessary to monitor carefully chlorination practice in drinking water distribution system of Marivan city and to ensure that the residual chlorine is available at consumer end.