A bifunctional RuO2-IrO2/Pt electrocatalyst for the unitized regenerative fuel cell (URFC) was synthesized by colloid deposition and characterized by analytical methods like TEM, XRD, etc. The result reveals that RuO2-IrO2 was well dispersed and deposited on the surface of Pt black. With deposited RuO2-IrO2/Pt as the catalyst of oxygen electrode, the performance of fuel cell/water electrolysis of unitized regenerative fuel cell (URFC) was studied in detail. URFC with deposited RuO2-IrO2/Pt shows better performance than that of URFC with mixed RuO2-IrO2/Pt catalyst. Cyclic performance of URFC with deposited RuO2-IrO2/Pt is very stable during 10 cyclic tests. (c) 2006 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.