A steering lock device (1) comprising a lock member (8) disposed in a housing (3); a slider (6) disposed in the housing that is slidable in a direction perpendicular to a moving direction of the lock member; a sloped portion (64c) and a sloped hole (71) being coordinated with each other in response to sliding of the slider to shift the lock member between the lock position and the unlock position; and a slide portion (32) and an auxiliary slide portion (33) each of which is disposed between the slider and the housing, the slide portion (32) including a guide rail (3d) and a rail receive groove (64f), and the auxiliary slide portion (33) including a guide pin (61b) and an auxiliary guide groove (3m) to accommodate the guide pin slidably.