To provide a buff polishing machine capable of conveying a workpiece flatly without scratching it and pouring water and washing it efficiently.

A pair of workpiece hold members 14, 14 are provided across a conveyance passage between a buff roll 11 and a back-up roller 12 and conveyance pinch rollers 13, 13. The workpiece hold member 14 is constituted by a water-tight chamber 15 and a brush part 16 and nips a workpiece 20 from both sides and holds it flatly when the workpiece 20 is conveyed. Moreover, water in the water-tight chamber 15 is poured through a pouring hole while the workpiece 20 passes between the workpiece hold members 14 and 14.