The work aims to improve footprint extraction capability of the BOPET aluminum-plating film in electrostatic field by studying adsorption capacity of a biaxially-oriented polyester film (BOPET) surface in high voltage electrostatic field. High voltage electrostatic field was applied to the surface of BOPET-based Al-coated film with a common electrostatic footprint extractor for dust footprint extraction use. Distance between electrode and the Al-coated film was controlled, and absorption efficiency of the film in electrostatic field was characterized with different sized SiO2 particles. Film microstructure was studied with optical microscope, electron microscope, XRD analysis technology and precision analytical balance. Causes affecting electrostatic adsorption capacity of the film surface in high-voltage electrostatic field were analyzed. Factors leading to the changes were discussed as well. The BOPET film would push down object surface in electrostatic field, the compaction and electrostatic adsorption force were significantly associated with carried charge. The adsorption capacity of film surface significantly improved as carried charge of the particles increased. Reducing the distance between the electrode and film could increase electric field intensity near the film, which was an effective way of improving the surface electrostatic adsorption capacity. The BOPET-based Al-coated film will constitute a plate condenser with the ground beneath in high-voltage electrostatic field. Electrical charge carried by the particles in electrostatic field is significantly related to particle shape. Microparticles carried much more electric charge, hence adsorption mass gain rate of the BOPET film surface is the highest. As the distance between the electrode and film increases, the electric field intensity decreases, electric quantity carried by particles declines and adsorption mass gain rate decreases rapidly. The greatest change in elec-trostatic adsorption capacity of electric field to different particles is present in the distance of 15~10 mm.