PURPOSE: To efficiently polish a roller glossed to an internal surface of a small recessed surface groove in the bottom surface by filling the inside of a barrel tank with an amount of abrasive stones in the vicinity of a position, where a row of the grooved roller is concealed, and moving the barrel tank.

CONSTITUTION: A plurality of rollers 6 with grooves 7 to be worked are mounted in series on a jig 9, and a plurality of the jigs 9 are rotatably supported to be arranged in a barrel tank 1 of a barrel machine in parallel to shafts 2a, 2b of the barrel tank 1 further with an equal space on the concentrical circumference. Next, the inside of the barrel tank 1 is filled with an amount of abrasive stones in the vicinity of a position of concealing a row of the grooved roller 6. An amount of water in use is in the vicinity of an upper surface of the abrasive stone in the case of placing the barrel tank 1 in a stationary condition, and the grooved roller 6 is fluidized to be polished by the abrasive stone by moving the barrel tank 1.