The identification of bacteriologically characters of coastal areas is important due to the fact that bacteriological pollution, transported to seas via rivers is a potential threat for ecosystem, animal and human health. In this study, bacteriological load of Çırpıcı River transporting to the Sea of Marmara from Zeytinburnu location in Istanbul and its relationship with primary hydrographic parameters investigated. The levels of fecal coliform (FC), total coliform (TC), fecal streptococci (FS) and total heterotrophic aerobic bacteria (HPC) tested using Membrane Filtration Technique in the surface water samples. Seawater temperature, pH, salinity, dissolved oxygen were recorded in-situ using multiparameter (YSI556 MPS). While the highest TC detected to be 13x107 CFU/100 ml, the highest FC was 14x106 CFU/100 ml. The lowest FC recorded as 25x10 CFU/100 ml. While the highest FS level was determined to be 73x105 CFU/100 ml, the highest HPC was 14x106 CFU / ml. Variable environmental parameters recorded for seawater temperature between 10.3-29.5˚C; pH 6.0-8.38; dissolved oxygen 0.34- 10.71 mg /l and salinity 16.50-26.57 psu during the study period. Significant correlation between the temperature and FC, FS and THAB detected. The levels of bacteria detected at the spot where the Çırpıcı River poured into the Sea of Marmara were found higher than the station at the 800 m open of the Sea of Marmara. It was determined that the Çırpıcı River carried 103 CFU bacterial loads at 100 ml for TC to the Sea of Marmara. The FC and FS counts carried to the Marmara Sea from Çırpıcı River recorded to be 102/100 ml and 103/100 ml, respectively. The fact that FC and TC levels were above the limit values during the study indicate the stability of pollution sources in the region and that the Çırpıcı Stream carries a bacteriological risk in terms of human, animal, and environmental health.