The invention provides a coupling agent smearing and clearing device which effectively solves the problems that in existing ultrasonic inspection, coupling agent is not uniformly smeared, paper is wasted when a coupling agent is cleared after inspection, efficiency is low, and operation is complex. According to the technical scheme, the device comprises a shell, wherein a rotating shaft is arranged on the lower side of the shell, T-shaped plates are arranged on the rotating shaft, arc-shaped plates are arranged on the outer side of the rotating shaft, soft fibers are arranged on the outer sides of the arc-shaped plates, movable plates are arranged on the arc-shaped plates, an annular plate is arranged on the rotating shaft, arc-shaped grooves are formed in the movable plate, and pins are arranged on the movable plates; a planetary gear train is arranged at the front end of the rotating shaft, a planetary carrier is fixed, the front end of the rotating shaft is fixed to a sun gear, cylinders are arranged on the front side and the rear side of the rotating shaft, the cylinder at the front side is coaxially fixed to a gear ring, the cylinder at the rear part is coaxially fixed to therotating shaft, wheels are arranged on the cylinders, clamping grooves are formed in inner rings of the wheels, and clamping pins are arranged on the side walls of the cylinders; a discharging grooveis formed in the shell, a sliding plate is arranged on the shell, and a through groove is formed in the sliding plate. A vertical plate is arranged at the lower side of the right end of the shell, a container is arranged at the lower end of the vertical plate, and a long-strip plate is arranged on the right sides of the arc-shaped plates.