Non-noble metal decoration is a promising strategy for promoting semiconductor photocatalysis by effectively enhancing charge separation. Cube-like WO₃-Cu hybrid was successfully synthesized by a facile ascorbic acid reduction method at room temperature. The composition and morphology characterization showed that the Cu particle was deposited on the surface of WO₃ nanocube. The WO₃-Cu-1.0 hybrid (when 1.0 mmol CuSO₄∙5H₂O was involved into the reaction system) exhibited promoted photocatalytic capability towards Congo Red photodegradation under simulated sun light irradiation. The trapping experiments of active species during photocatalysis and ESR spectra of DMPO•OH signal of WO₃-Cu-1.0 composite confirmed that the photogenerated holes (h ⁺), •OH, and •O₂^-were the predominant active species during Conge Red degradation. Based on the photo/electro-chemical measurements, it was proposed that efficient charge transfer was accomplished between the WO₃ nanocube and Cu nanoparticles, which promoted electron-holes separation and subsequently photocatalysis reaction in the Congo Red solution. This work provides a facile preparation method for a binary photocatalyst system in which a semiconductor coupled with non-noble metal.