Provided is a webbing winding device having a lock mechanism in which a driven body is less influenced by an inclination of a driving body. A peripheral wall extends from an edge portion of a penetration hole formed at a sensor gear constituting the lock mechanism toward a link member, and a guide hole is formed at a bottom wall formed at the front end of the peripheral wall. An engagement pin of the link member passes through the guide hole from the base end portion rather than the front end portion thereof in the protruding direction. Further, in the front end side of the engagement pin passing through and protruding from the guide hole, the outer peripheral portion is spaced apart from the inner peripheral portion of the peripheral wall.