The invention discloses a flexible magnetic absorption underwater wall climbing robot, Including a duplex stainless steel body, a Flexible-magnetically-attractive crawler travel device and a magneticforce compensation device, magnetic compensation devices are arrange at that front and rear of the airframe respectively, A magnetic force compensation device comprise a lifting bracket, Universal wheels and magnets, A lifting bracket comprises a lifting plate, Left lifting lever, the middle lifting lever and the right lifting lever, Left lifting lever, the middle part of the middle lifting lever and the right lifting lever penetrate the lifting plate and are fixedly connected with the lifting plate, Left lifting lever, the intermediate lifting lever and the right lifting lever are slidablyinstalled on the machine body, A left lifting lever and a right lifting lever are sleeved with springs, The upper ends of the springs are against the body, the lower ends of the springs are against the lifting plate, the bottom of the left lifting rod and the right lifting rod are both provided with attractive magnetic blocks, and the bottom of the middle lifting rod is provided with a universal wheel, which can solve the technical problem of cleaning the ship surface adhesives under water when the ship is sailing on the water surface.