A novel method for perchlorate reduction by combination of adsorption and biological reduction was investigated in this work. After being adsorbed by biosorbent, the concentrated perchlorate was completely biologically reduced by mixed bacteria, which were dominated by Proteobacterial species. The reducing efficiency of perchlorate concentrated on biopolymer based adsorbent surface achieved optimal (75-85%) after 4 days of reduction time in the neutral environment (pH: 7.0-7.5). The reduction of perchlorate was enhanced by the Cl- and SO42- ions and weakened by the dissolved NO3- ions in the reduction system. Moreover, per gram biopolymer based adsorbent could uptake 134.9 and 102.4 mg of perchlorate in the first and second bin-regeneration cycles of column tests, with regeneration efficiency of 77.7% and 59.0%, respectively. In conclusion, results indicated that the reduction of concentrated perchlorate could be achieved simultaneously with the biosorbent bin-regeneration. (C) 2015 Elsevier B.V. All rights reserved.