Pure tungsten oxide (WO3) nanoparticles (NPs) and WO3/copper tungstate (CuWO4) nanocomposites (NCs) were prepared by varying copper content from (5–20 wt%) via the co-precipitation process. XRD results reveal that the structural parameters of WO3/CuWO4 NCs have been strongly affected via Cu doping. Morphology of synthesized WO3 was noticed to be distinct and particle size was significantly reduced through Cu doping confirmed by employing HRTEM studies. Elemental purity of as synthesized products, elucidated from EDX and XPS analyses, reveals that WO3/CuWO4 nanocomposites contain W, O and Cu elements only. Also, FT-IR spectra and its corresponding assignments indicate the existence of WO3/CuWO4. UV-Visible study shows that WO3/CuWO4 composites have narrow bandgap compared to pure WO3. Photoluminescence spectral peaks intensity of NCs displays a decreasing trend, which supports the enhanced photocatalytic activity. The results clearly show that 20 wt% Cu incorporated WO3 sample exhibits better photocatalytic nature than that of pure WO3 and will be more applicable in purify the water.