NOVELTY - A copper-indium selenium photovoltaic film preparation method involves weighing copper (II) chloride dehydrate, indium trichloride and selenium powder, and mixing the weighted materials with organic solvent. The mixture is transferred to a reaction kettle. The kettle is placed to a drying box. The product is washed, filtered and dried to obtain copper-indium selenium (CIS) powder. The powder is mixed with another organic solvent. Tackifying sol is added to black slurry and stirred to form CIS coating for preparing a CIS film by spin coating, spray coating, dipping-pulling or curtain coating.    USE - Method for preparing a CIS photovoltaic film for a solar battery.    ADVANTAGE - The method enables preparing the film with better quality, low cost and strong operability and practicability, so that the film is suitable for commercial production.    DETAILED DESCRIPTION - A CIS photovoltaic film preparation method involves weighing copper (II) chloride dehydrate, indium trichloride and selenium powder according to a stoichiometric ratio, and mixing the weighted materials with an organic solvent. The mixture is dispersed by ultrasonic wave, the dispersant is added to the mixture, and the mixture is transferred to a reaction kettle. The reaction kettle is sealed and placed to a drying box. Temperature of the drying box is maintained and cooled. The product is washed, filtered, and dried in a vacuum condition to obtain CIS powder. The CIS powder is weighted and mixed with another organic solvent. Modifier is added to the mixture. The mixture is dispersed by the ultrasonic wave, and the dispersed mixture is transferred to the sealed container. Grinding and dispersing processes are carried out in a wet manner to form a black slurry. Tackifying sol is added to the black slurry and stirred fully and uniformly to form the CIS coating. The CIS coating is used to prepare a CIS film by a spin coating, spray coating, dipping-pulling or curtain coating. INDEPENDENT CLAIMS are also included for the following:    (1) a powder for CIS photovoltaic film for solar battery    (2) a coating for CIS photovoltaic film for solar battery.    DESCRIPTION OF DRAWING(S) - The drawing shows a flow diagram illustrating a method for preparing a CIS photovoltaic film. '(Drawing includes non-English language text)'