Although perchlorate (ClO4-) is a trace of emerging contaminant in ground and surface water system, it has a detrimental effect on human health. Catalytic/electrocatalytic reduction has attracted increasing attention to remove ClO4- from water because of the fast and permanent conversion of ClO4- into innocuous chloride (Cl-). However, there are also many problems that hinder its implementation, i.e., the lower removal efficiency and catalytic activity to ClO4-, the poorer selectivity toward desired reduction products (Cl-), the easier deactivation of catalysts or electrodes. This paper critically reviews the state of knowledge in the field of catalytic/electrocatalytic reduction of ClO4- so as to find better methods to overcome these weaknesses. Specifically, the review summarizes the reported researches related to (1) proposed reaction mechanisms, (2) approaches to improve catalytic/electrocatalytic reduction of ClO4-, (3) inhibition and fouling of catalyst and electrode, (4) prospecting the advantages and barriers of this technology. This review will significantly improve the understanding of the detail processes and mechanisms of ClO4- reduction by catalysis/electrocatalysis and provide fundamental and useful information and data to scientific research and actual practice. (C) 2016 Elsevier B.V. All rights reserved.