The efficient photocatalytic degradation of methyl orange was achieved by exploring two simple copper(II) Schiff base complexes [{Cu(HL)(CH3OH)}2] (1) and [Cu(HL)2] (2) (H2L = N-salicylidene-2-aminoethanol) as photo-Fenton-like catalysts. Both 1 and 2 exhibited excellent catalytic performance without an acidification process, and the mononuclear complex 2 functioned better than the dinuclear complex 1. The results suggest that 2 is advantageous for catalyzing efficient degradation of azo dye and has potential application in the effective treatment of dye-polluted water.