Despite excellent catalytic capability, Cu₂O nanomaterial exhibits weak stability which limits its application. In this study, a novel kind of Cu₂O, Cu₂O/BNNSs-OH, supported catalyst with highly catalytic efficiency and stability, was facilely fabricated via a controllable liquid phase reduction of ascorbic acid and combining with an annealing process. Cu₂O/BNNSs-OH catalyst was synthesized by using boron nitride nanosheets (BNNSs), prepared by the “push-pull” effect of polyvinylpyrrolidone (PVP) and water phase change, as a supporter and spherical Cu₂O nanoparticles (2-7 nm) prepared by forward titration (ascorbic acid→Cu ²⁺, solution with a pH 11) as active components. Morphology and structure of as-obtained samples were characterized by scanning electron microscopy (SEM), high resolution transmission electronic microscopy (HRTEM), atomic force microscopy (AFM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy. The results of the synthetic method showed that spherical Cu₂O nanoparticles were uniformly dispersed on the carrier surface and BNNSs displayed some stabilization effect on Cu₂O which could be prevented from being oxidized into CuO. Moreover, the catalytic activity was investigated by catalytic reduction reaction of 4-nitrophenol to 4-aminophenol. Cu₂O/BNNSs-OH with high catalytic activity similar to the noble metal catalyst for the reduction of 4-nitrophenol is highly reusable for five successive cycles without significant degradation and activity loss.