Some pathogenic bacteria found in drinking water may cause infections in many countries. The control of these infections is done by water treatment. It's very important to monitor faecal and total coliform bacteria for the examination of microbiologic quality of drinking water. In addition, the determination of total mesophilic aerobic bacteria growing in 22 - 37 ºC is also used in measure of bacterial pollution.              In our study 88 bottled water belong 22 different brands were examined. The samples of water that are taken from plastic bottles of 19 L were examinated for total mesophilic aerobic bacteria, faecal coliform, total coliform, Aeromonas spp., Pseudomonas spp., presence of free living amoeba. Faecal coliform, total coliform, Aeromonas spp., Pseudomonas spp. and the existence of free living ameoba is determined by membrane filtration; and the total mesophilic aerobic bacteria numbers determined by pour plate method.             It has been found that all of the examined samples of this study are not acceptable according to the standarts of TSE, EPA and WHO. Although we took four different samples from the same brand, we found level of different pollutions. Resumably, method of cleaning up the bottles and the unhealthy conditions of filling facilities might cause these differences.             In conclusion, our study showed that ıt's very important that the systematic microbiological monitoring and control of bottled water which is used as drinking water. Also this control should be done by authorized foundations filling facilities and bottled water.