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9Deinococcus radiodurans, the most radiation resistant organism ever known, has 1 0 gained importance in recent years as a potential candidate for bioremediation of heavy 1 1 metals, especially radioactive ones. This study investigates the efficiency of a recombinant D.1 2 radiodurans (DR1-bf + ) strain with an ability to form biofilm for uranium remediation. In this 1 3 study, a modified Arsenazo III dye method was used to estimate the uranium concentration. 1 4 Uranyl nitrate aqueous solution, wherein U exists as uranyl ion (UO 2 +2 ), is generated during 1 5 the operation of nuclear fuel reprocessing. The D. radiodurans biofilm (DR1-bf + ) grown in 1 6the presence of 20 mM Ca 2+ ion showed phenomenal ability of uranyl ion removal. DR1-bf + 1 7 (+Ca 2+ ) biofilm removed ~75 ± 2% of 1000 mg/L uranium within 30 minutes post treatment 1 8 from uranyl nitrate aqueous solution. U removal rate was also found to be directly 1 9proportional to biofilm age. This study discusses the extraordinary ability of D. radiodurans 2 0 biofilm in uranium removal. 2 1