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Different groups of bacteria live in radioactive environments and microbial diversity of these regions depend on their geographical conditions. Overall, little is known about the bacterial diversity of naturally radioactive regions in Iran and the aim of this study was to investigate the biodiversity of radiation-resistant bacteria in a radioactive site in Ramsar, Iran. The soil samples were collected from the radioactive site and the samples were exposed to various doses of gamma radiation using a Co-60 source. After exposure, the samples were spread on TGY agar, and the surviving bacteria were purified and preserved for further studies. The 16S rRNA gene sequencing and the UV-Gamma radiation-resistant level of each strain were determined. After radiation and the cultivation of the soil samples, two Gamma and UV radiation-resistant, Grampositive, yellow-pigmented, cocci, strictly aerobic, and catalase-positive bacterial strains were isolated. Phylogenetic analysis, based of 16S rRNA gene sequences, showed that the strains belonged to the Kocuria sp. and the Dermacoccus sp. In addition, both strains were resistant to >15 kGy of gamma radiation and >300 J m(2) UV radiation. An analysis of these strains constitutes the first report on radioresistant bacteria belonging to the K. rhizophila and D. nishinomiyaensis isolates recovered from the radioactive region in Iran. In addition, due to the radiation-resistant characteristic of our strains and their antioxidant activity properties, we supposed that these isolates could be ideal candidates for industrial and bioremediation applications.