The objectives of this study are: to study the feasibility of reduction of perchlorate by metal iron in the presence of ultraviolet (UV) radiation as a catalyst under anoxic environment; and, to study the effectiveness of iron oxides and metallic iron on removing perchlorate in the presence of phosphoric acid. An ion chromatograph was used to determine the perchlorate and other oxychlorine species in this study. A new method with varying eluent concentrations was developed to identify and quantify the species resulted perchlorate reduction. A Rayonet(R) photochemical chamber and 800 mL quartz reactor were used to study the UV effect on perchlorate reduction. In order to mimic the groundwater system, samples of degassed-deionized water was purged by nitrogen gas before use. The reactor was operated as batch; however, the contents were continuously circulated by a Masterflex(R) hydraulic pump to provide complete mixing.