The invention discloses a silane metal surface treating agent which comprises the following components in parts by weight: 15-18 parts of a silane coupling agent; 22-26 parts of a film-forming agent;4-6 parts of a chelating agent; 25-30 parts of water; 1-3 parts of a corrosion inhibitor; 2-4 parts of a penetrating agent; and 0.5-3 parts of a lubricant. The silane metal surface treating agent disclosed by the invention has excellent adhesive force and salt spray resistance.