The invention discloses an automatic film coating device for a lead acid storage battery box. The automatic film coating device comprises a lead acid storage battery box conveying line. A lead acid storage battery box push mechanism for pushing lead acid storage battery boxes to the lead acid storage battery box conveying line is arranged at an inlet side of the lead acid storage battery box conveying line. A push plane of the lead acid storage battery box push mechanism is parallel and level with a conveying plane of the lead acid storage battery box conveying line. A film passing gap for passing of the film is arranged between the lead acid storage battery box push mechanism and the lead acid storage battery box conveying line. An automatic film conveying mechanism is arranged above the film passing gap. A film head clamping device is arranged below the film passing gap. The automatic film coating device has a simple structure and low cost.