WO3 nano-films were synthesized on the conductive glass substrate by hydrothermal method. WO3/Bi2WO6 composite films were prepared by solvothermal method with different solvothermal reaction time (6 h, 8 h, 10 h) based on WO3 nano-films, and X-ray diffraction and scanning electron microscopy were used to characterize WO3/Bi2WO6 composite film samples. The WO3/Bi2WO6 composite film samples were tested for absorption spectroscopy, photocurrent, photoelectrocatalysis and alternating current impedance. The results show that the WO3/Bi2WO6 composite film samples have a wider spectral response range, higher photocurrent density and significantly improved photoelectrocatalysis efficiency than pure WO3 nano-films, and the WO3/Bi2WO6 composite film samples with a solvothermal reaction time of 8h have the highest photocurrent density and the best photoelectrocatalysis efficiency. The WO3/Bi2WO6 composite film effectively reduces the internal electronic impedance, increases the effective photoelectrochemical reaction sites, significantly improves the photoelectrochemical property, and can be well applied in the field of photoelectrocatalysis.