摘要:The experiment was carried out to determine the presence and numbers of arsenic resistant bacteria population. In this study, soil samples were collected from different contaminated sites of Khulna shipyard, Rupsha, Baghmara and Ramnagor in Khulna district of Bangladesh. Twenty arsenic resistant bacterial strains were isolated from the soil samples. They were isolated by growing them on Nutrient Broth (NB) medium impregnated with high concentration of arsenic. From them, six strains Bacillus lichnefomis (1/10), Listeria murrayi (2/9), Bacillus polymyxa (3/6), Moraxella urethralis (4/9) and Planococcus citreus (5/8) and Pseudomonas fluorescens (6/8) were finally selected and studied their morphological and biochemical characters in details. All six strains were able to tolerate very high concentration (>100 ppm). The optimum pH and temperature for the growth of all six strains were 8.5 and 37°C, respectively. It was concluded that bacteria living in arsenic free environment must posses a mechanism necessary to resist other toxic levels of arsenic.