The utility model discloses a roof waterproof structure comprising a basic purline, sunlight plates and a color steel plate. The color steel plates are arranged on the basic purlines via a color steel bearer; a bearing skeleton forming a step-shaped structure with the basic purline is arranged on the basic purline; the sunlight plates are mounted on the bearing skeleton; and a flashing plate is arranged on the bearing skeleton and covers a gap between the sunlight plates and the color steel plate, so water leakage of the gap between the sunlight plates and the color steel plate can be prevented. The roof waterproof structure can be easily detached and maintained; when maintenance is required for the sunlight plates, the sunlight plates can be conveniently replaced as long as the flashing plate is removed; and no damage is caused to the adjacent color steel plate, so maintenance cost is reduced.