The invention relates to a preparation method of visible light responded WO3 / {001}TiO2 composite photocatalyst. The preparation method comprises the following steps: by adopting an improved sol-gel method, firstly preparing {001} surface-exposed anatase TiO2 at room temperature, then depositing a certain amount of WO3 on the surface of the anatase TiO2 to construct a WO3 / {001}TiO2 composite system. according to the preparation method, the {001} surface-exposed anatase TiO2 is prepared by adopting the simple sol-gel method, so that the original preparation concept of inhibiting the hydrolysis of a titanium-containing precursor can be changed, the amount of water is increased to promote the complete hydrolysis of butyl titanate and inhibit the polymerization, the original feeding sequence is changed, butyl titanate is dropwise added into an HF water solution, uniform {001} surface-exposed anatase TiO2 can be formed at room temperature, the preparation technology is simple, the reaction conditions are mild, the reaction speed is easily controlled, the cost is low, and the preparation method is suitable for industrial popularization and application.