PURPOSE: To prevent falling off of a belt from a pulley while this is traveled obliquely with the pulley and to prevent its slipping and contacting by sliding during its traveling.

CONSTITUTION: In a pulley for an obliquely traveled belt, in which a belt 13 is placed so as to travel obliquely by a specified angle against a pulley rotation axial center X, a plurality of plate-like sliding members 3 to 10 are cylindrically arranged in the peripheral direction of a pulley main body so as to surround the entire outer periphery thereof. Each of the plate-like sliding members 3 to 19 is engaged with the pulley main body by a hinge and a hinge groove so as to be slid only in the pulley rotation axial center X direction. By sliding each of the plate-like sliding members 3 to 10 coming into contact with the belt 13 in the pulley rotation axial center X direction, the lateral sliding of the belt is prevented.