A steering lock device for use with a steering shaft, the steering lock device comprising: a lock bar moved between an engagement position where the lock bar is engaged with the steering shaft and a non-engagement position where the lock bar is disengaged from the steering shaft,wherein the lock bar has a basal end including a recess; a stopper including an engagement portion wherein the lock bar is configured to be coupled to the stopper, when the recess engages the engagement portion, so that the lock bar and the stopper are movable integrally with each other in the locking direction and the unlocking direction; a camshaft that is rotated in response to a locking operation and an unlocking operation, wherein the camshaft includes a lock actuation cam projecting from a first axial position of the camshaft in a radial direction and having a cam surface, which comes into contact with the stopper to move the lock bar to the engagement position in the locking direction, and the lock actuation cam is configured to prohibit rotation of the steering shaft when the lock bar is engaged with the steering shaft; and a housing configured to be fixed to a steering column that accommodates the steering shaft, wherein the housing includes a component receptacle that accommodates the lock bar, the stopper, and the camshaft, and that includes shaft seats; and a key cylinder coupled to the camshaft in the housing, the steering lock device being characterized by a counterweight located at a second axial position of the camshaft that differs from the first axial position, wherein the counterweight projects from the second axial position of the camshaft in the same radial direction as the lock actuation cam, and wherein the counterweight is configured to prevent or limit unintended rotation of the camshaft in a state in which the camshaft is coupled to and rotatably mounted on shaft seats of the housing after the lock bar is coupled to the housing and before the stopper is coupled to the housing, thereby stabilizing the camshaft at an initial angular rotation position in the housing before the camshaft is coupled to the key cylinder. a lock bar moved between an engagement position where the lock bar is engaged with the steering shaft and a non-engagement position where the lock bar is disengaged from the steering shaft,wherein the lock bar has a basal end including a recess; a stopper including an engagement portion wherein the lock bar is configured to be coupled to the stopper, when the recess engages the engagement portion, so that the lock bar and the stopper are movable integrally with each other in the locking direction and the unlocking direction; a camshaft that is rotated in response to a locking operation and an unlocking operation, wherein the camshaft includes a lock actuation cam projecting from a first axial position of the camshaft in a radial direction and having a cam surface, which comes into contact with the stopper to move the lock bar to the engagement position in the locking direction, and the lock actuation cam is configured to prohibit rotation of the steering shaft when the lock bar is engaged with the steering shaft; and a housing configured to be fixed to a steering column that accommodates the steering shaft, wherein the housing includes a component receptacle that accommodates the lock bar, the stopper, and the camshaft, and that includes shaft seats; and a key cylinder coupled to the camshaft in the housing, the steering lock device being characterized by a counterweight located at a second axial position of the camshaft that differs from the first axial position, wherein the counterweight projects from the second axial position of the camshaft in the same radial direction as the lock actuation cam, and wherein the counterweight is configured to prevent or limit unintended rotation of the camshaft in a state in which the camshaft is coupled to and rotatably mounted on shaft seats of the housing after the lock bar is coupled to the housing and before the stopper is coupled to the housing, thereby stabilizing the camshaft at an initial angular rotation position in the housing before the camshaft is coupled to the key cylinder.