The invention discloses a preparation method of a polyvinylidene fluoride (PVDF) adsorption film and belongs to the technical field of water treatment films. The preparation method comprises that PVDF as a main film material is modified and is used for combination with a functional organic compound, the surface of a liner tube is coated with the functional organic compound, and the surface of an adsorbent is coated with the modified PVDF so that the PVDF adsorption film is obtained. The PVDF adsorption film can be used for removing heavy metal ions such as copper, mercury, cadmium and nickel in water. The functional organic compound in the adsorption film is a chelating agent with a strong metal ion bonding capability. Through the PVDF adsorption film, the hydrophilic PVDF and the adsorbent are combined so that water is produced without external pressure and the PVDF adsorption film has effects of adsorption and filtration and characteristics of large adsorption capacity, high adsorption efficiency and easy desorption in an acidic solution. The preparation method has simple processes and a low cost.