To provide a surface polishing machine capable of easily responding to the enlargement of a glass plate, polishing with high accuracy, and shortening a tact time without taking time and effort for mounting the plane material.

A polishing roller 20 is disposed at the lower side of a transfer route 10 horizontally transferring the glass plate (plane material) W, and a press roller 30 is disposed at the upper side of that, and a polishing pad 21 disposed at the outer periphery of the polishing roller is rotated and contacted to the lower surface of the glass plate at the faster speed than the transfer speed. A polishing liquid reservoir tank 40 is provided at the lower part of the polishing roller, and the polishing liquid 41 adheres to the polishing pad with wet contact. A cleaning means 50 and a dressing means 60 are disposed at the surrounding of the polishing roller after polishing. The press roller is incorporated with a mechanism which finely adjusts the outside diameter of the outer peripheral pressure contact layer 31 by the introduction pressure of the air from the inner peripheral side.