Abstract: A wire saw having a wire gradually moved from a wire feeding unit to a wire withdrawing unit by a reciprocal movement of the wire on a group of rolls caused by the movement of movable rollers toward or away from fixed rollers, and in which the transmission of a drive force to a roll of the group rolls is performed by using an endless transmission strip wound around movable guide rings and fixed guide rings, and the movements of the movable rollers toward or away from the fixed roller and of the movable guide rings toward or away from the fixed rings are simultaneously performed in a rectilinear direction both upstream and downstream of the roll group.