Wall painting device and painting method

The invention relates to the technical field of building decoration, and discloses a wall painting device which comprises a movable seat, a processing barrel used for stirring painting paint is fixedly connected to the outer portion of the movable seat, and a fusion cover used for preliminary contact and mixing of the paint is fixedly connected to the outer portion of the processing barrel. Negative pressure is generated in a corrugated pipe through an electric pump, putty powder raw materials and glue raw materials are sucked through a suction head and conveyed into a fusion cover and a processing barrel, and a paddle shaft rotates to sufficiently stir the mixed putty powder raw materials and the mixed glue raw materials in the processing barrel to form putty powder coating. The integrated operation of feeding proportioning, mixing and conveying of coating raw materials is achieved, meanwhile, the darby plate slides on the inner side of the positioning plate to adjust the wall painting distance, so that the