A miter saw having a holder fixing mechanism for fixing a pivot posture of a holder. The holder supports a support section on which a saw blade section is pivotally movably supported. The holder is laterally pivotally movable about a holder shaft to change angle of a side surface of a circular saw blade relative to an upper surface of a base. The holder fixing mechanism includes a clamp bolt whose axis is directed perpendicular to the holder shaft and in parallel with the side surface of the circular saw blade. By the rotation of the clamp bolt about its axis, a fixing relationship between the holder and the base section is established.