Disclosed is a rust-preventive composition comprising (A) an aromatic compound i) containing a group selected from the group consisting of an —N═N— group, a >C═N— group, a >C═O group and an —N═O group and ii) having an absorption band in a visible region of from 530 nm to 750 nm; (B) a colloidal silica; (C) a film-forming polymeric compound containing in one molecule a group selected from the group consisting of an —OH group and a —COOH group; and (D) an organic solvent. This composition, having been coated on metal surfaces, provides a sufficient corrosion resistance without making any chromating treatment.