The invention provides an anti-electric wall cover module and a water heater. The anti-electric wall cover module comprises an anti-electric wall cover, and a back shell arranged in the anti-electricwall cover. The anti-electric wall cover is provided with a mounting plate facing users; an opening is formed in the position, near the shell, of the anti-electric wall cover; and a transverse rib extending in a preset direction is arranged in the position, near the opening, of the mounting plate. The back shell comprises a main body, and a fixed part arranged on the main body; an accommodating cavity for accommodating an operation panel is surrounded between the main body and the mounting plate; and the main body is fixed on the mounting plate by the fixed part. The edge, near the opening, ofthe main body abuts against the bottom surface, deviated from the opening, of the transverse rib; and the size of the transverse rib in the preset direction is larger than or equal to the size of themain body in the preset direction. In the anti-electric wall cover module and the water heater, the transverse rib can stop water currents entering the anti-electric wall cover from a gap between theshell and the anti-electric wall cover, so that the water currents are prevented from entering the accommodating cavity of the operation panel, the service life of the operation panel is prolonged, and the waterproof performance of the water heater is improved.