In a retractor with a clamp mechanism for holding a webbing directly in a vehicle emergency, the retractor provides a movable clamp member for holding the webbing between the lower plate and the clamp member, and a guide member for guiding the clamp member to a webbing holding position, in which the clamp member includes a clamp teeth portion for clamping and engaging the webbing with a webbing opposing surface of the clamp member, a plane portion located on an opposite side to the webbing opposing surface, and a rear end side edge provided on a rear end side of the plane portion, and in which the guide member includes a sliding contact surface for sliding contact with the plane portion of the clamp member and a deforming portion deformable substantially in parallel to the webbing opposing surface of the clamp member. A movable wedge-shaped clamp member may be provided with a hold portion including a clamp teeth portion formed in a shape capable of biting into a surface of the webbing and shearable and deformable by a tensile force of a predetermined value or greater, and including a pressure teeth portion capable of applying resistance to the webbing moved in the webbing draw-out direction by a tensile force of a predetermined value or greater.