The invention belongs to the field of titanium dioxide detection, and particularly relates to a preparation method of an ink titanium dioxide film. In order to solve the technical problem, the preparation method of the ink titanium dioxide film comprises the following steps of mixing and uniformly dispersing glass beads, titanium dioxide and polyurethane to form ink slurry, coating a PP (polypropylene) film or a BOPP (biaxially-oriented polypropylene) film with ink slurry via a wire rod by an automatic coating instrument, and drying the prepared film. According to the method, film coating can be more precise, and artificial film coating nonuniformity is reduced.