Halophilicity of bacteria may play a role in their capability for absorption of heavy metals and oxianions. In this study, 67 isolates from a soil sample (Gaw-khooni marsh) were isolated by cultivation on salty (5%) and salt-free nutrient media. Salt-dependency of bacteria was investigated. Thereafter, halophiles and halotolerants were differentiated from each other. Selected strains were studied through cesium-biosorption experiments. To do this, primary and secondary precultures were prepared through cultivation in flasks and incubation in a shaking incubator at 30oC and 150 rpm. Constant amounts of centrifuged and washed cells were added into solutions containing 200 mg Cs 1-1.Then treated cells were separated and the remaining cesium concentration was measured by AAS method. Maximum absorption was observed in one of halotolerant strains (67.3 mg/gdw) and the minimum was observed in halophilic strain (13.9 mg/gdw). The results showed that the halotolerants possesses increased absorbing capacity, (with average amount of 33.1 mg/gdw) than those of halophilic bacteria (15.6 mg/gdw).