The possibility to activate cis-ReOBr3(PPh(3))(2) (inactive under homogeneous catalysis conditions) by photoimmobilization on different supports is demonstrated. The systems obtained are active in the liquid-phase hydrogenation of 1-hexene and m-nitrobenzoic acid. We propose various mechanisms for grafting the complex in darkness and under UV irradiation. The samples photoimmobilized on anatase are the most active.