To provide a high temperature mechano-chemical polishing method and a device, mechano-chemically polishing a work piece at a high temperature in an open atmosphere, facilitating approach to a work piece in the process of polishing, a polishing plate and abrasive grains, having high workability, and remarkably heightening the machining efficiency.

The work piece 1 is held by two flat plates (a polishing plate 12 and a work holding plate 16), one or both of the flat plates are heated to raise the temperature of the work piece, and while fine particles 2 causing mechano-chemical action are supplied between the work piece and at least one flat plate, the work piece is mechano-chemically polished at a high temperatures.