PURPOSE: To prevent deterioration of surface roughness even in machining for a long period of time with a roller burnishing machining device to mirror finish and machine an outer peripheral surface of a pipe, bar, wire, etc.

CONSTITUTION: A discharge hole 9 to discharge dust and machining powder or the discharge hole 9 and a discharge induction groove 10 are provided on a head 4 arranged in an outer periphery of rollers 3 on a roller burnishing machining device to mirror finish an article to be machined by crushing a protruded part on an outer peripheral surface of the article to be machined by a plural number of the rollers 3 rotating while pressurizing the outer peripheral surface of the article 1 to be machined.