Bacteria in sea sediments play a fundamental role in organic matter decomposition, in several geochemistries transformations, in nutrient regeneration and as a nutritious source for the benthic fauna. Bacterial studies, in sediments of coastal environments, are important due to the intense anthropic activity in these areas. The objectives of the present research were to study in sediments of intertidal areas (sandy beaches and mangroves), of Guaratuba Bay: the variation of total heterotrophic bacteria, bacterial biomass, halophilic and halophobic heterotrophic bacteria, total coliforms, Escherichia coli, and the interrelation between biotic and abiotic factors. High values of total heterothrophic bacteria, bacterial biomass, total coliforms and E. coli were observed in two stations of sandy sediment intensely impacted, located close to the oldest area of Guaratuba city. In the inner stations, located in mangrove areas, high values of halophilic and halophobic aerobic cultivable bacteria, total coliforms and E. coli were also observed. The results show that high values, mainly of total heterothrophic bacteria, total coliforms and E. coli can also be found in polluted sandy sediments. Therefore, we suggest that microbiological analyses of sediments to be mandatory in the legislation for monitoring balneability and/or for the cultivation of organisms that may be subject of raw consumption.