PURPOSE: To efficiently manufacture products, the dimensional precision and the shape precision of which are extremely high at a low cost without damaging a work in achieving the finishing the work by free abrasive grain.

CONSTITUTION: A square-shaped or spiral groove 3 is provided or a number of partitioning holes are made on the surface to be machined of a finishing tool, and a synthetic string 5 is stretched or a paper is placed according to the shape of the groove on the surface to be machined. When the surface to be machined is placed on the surface of a work 10 to be finished to execute the relative movement, the abrasive grain is smoothly held by the synthetic string 5 or the paper and the surface of the work 10 is polished thereby. When a strong force is applied to the abrasive grain, the abrasive grain is separated from the synthetic string 5 or the paper, and retracted in the groove 3 of the surface to be machined or in the partitioning holes, preventing the work 10 from being damaged.