The present invention provide drainage metal surface treatment agent and using the metal surface treatment processing of metal materials, the drainage metal surface treatment agent is used for forming can prevent metal materials and laminated film or a resin film stripping, and closed sex and drug resistance and retention excellent surface treatment by membrane. Drainage metal surface treatment agent of the present invention contains: polyvinyl alcohol compounds (A) and one or more than two crosslinking compounds (B), in the crosslinking compounds (B) has with polyvinyl alcohol compounds (A) crosslinking reaction of functional groups (B1), and contain vocs can react with polyvinyl alcohol compounds (A) the elements of the crosslinking of inorganic compounds (B2).