We report on the characteristic anion-exchange behavior of the superheavly element dubnium (Db) with atomic number Z = 105 in HF/HNO3 Solution at the fluoride ion concentration [F-] = 0.003 M. The result clearly demonstrates that the fluoro complex formation of Db is significantly different from that of the group-5 homologue Ta in the 6th period of the periodic table while the behavior of Db is similar to that of the lighter homologue Nb in the 5th period.