As visible light photocatalysts, narrow bandgap semiconductors can effectively convert solar energy to chemical energy, exhibiting potential applications in alleviating energy shortage and environmental pollution. Cu₂O/Cu hollow spherical heterojunction photocatalysts were prepared by one-pot solvothermal method without any template using CuCl₂·H₂O as precursor, H₃NO·HCl and NaBH₄ as reducing agents. Morphologies, crystal structures, composition, specific surface areas, and optical properties of the products were analyzed. Addition of NaBH₄ gradually changes the morphology of Cu₂O/Cu from hollow truncated octahedra to hollow nanospheres. Thickness of Cu layer on surface of Cu₂O can be easily controlled by tuning amount of NaBH₄. Direct reduction of Cu₂O by NaBH₄ leads to intimate contact between Cu₂O and Cu interfaces, which is favorable for carrier separation and transport. Meanwhile, surface plasmon resonance effect of Cu promotes the absorption capability of Cu₂O/Cu to visible light, thus the prepared hollow sphere Cu₂O/Cu particles exhibit a higher photodegradation capability for methyl orange (MO) and colorless enrofloxacin (ENR). Catalytic performance of Cu₂O/Cu is very stable, with no significant change in its photocatalytic efficiency for MO after five recycles. Free-radical removal experiments indicate that ∙O₂^- and holes were dominant species during the MO degradation. Higher photodegradation capability of Cu₂O/Cu for MO is attributed to synergistic effect of Cu₂O and Cu. This study provides a promising strategy for preparation of heterojunction photocatalysts.