A polygonal barrel spattering device and a polygonal barrel spattering method for applying superfine particles smaller in particle size than particles or thin-film on the surfaces of the particles, coated particles formed by the device and method, a micro capsule, and a method of manufacturing the microcapsule. The polygonal barrel spattering method comprises the steps of storing the particles (3)in a vacuum container (1) with an inner part cross section of polygonal shape at a position generally parallel with a gravitational direction and performing spattering while agitating or rotating theparticles (3) in the vacuum container (1) by rotating the vacuum container (1) about a rotating axis positioned generally in a direction vertical to the cross section. Thus the superfine particles smaller in particle size than the particles or the thin-film can be applied onto the surfaces of the particles (3).