An efficient CuO anchored ZnO nanoflakes were synthesized through facile wet chemistry method and the catalysts were well characterized using various sophisticated instruments. CuO nanoparticle incorporation was found to have a direct linear relationship with light absorbance. The degradation ability of the ZnO/CuO p-n junction was studied on the degradation of methyl orange. Under UV–Vis light illumination, the photocatalytic removal efficacy of methyl orange over CuO/ZnO p-n junction is up to 89%, which is greater than that of barecatalysts. The maximized photocatalytic degradation performance might be ascribed to the augmented visible light harvesting capacity and reduced the rate of photogenerated electron-hole pair recombination. The efficient photoinduced electron and hole pair charge separation upon excitation is aided by the effective formation of p-n junctions between ZnO and CuO. Based on the findings, a plausible photocatalytic mechanism for the as-synthesized CuO anchored ZnO nanoflake was proposed.