PURPOSE: To efficiently polish a front surface material of flat or irregularly engraved building materials, fittings, furnitures.

CONSTITUTION: On the upper part of a material feeding device a rotary sanding device 1 is provided upstream of it while a belt sanding device 2 is provided downstream of it. A rotary brush-like paper sander 8 wherein a plurality of sand papers in which rectangular flaps are radially and projectingly formed are stacked is inserted into the rotary-type sanding device, and an endless fabric sandpaper sheet 14 wherein a thick nonwoven fabric wherein abrasive grains are deposited on its front surface is stuck on the base member cloth (or paper) is laid in the belt sanding device, and a cubic or flat surface of a wood material is polished with one process.