A seat reclining apparatus includes a base member; a pivot member having an internal tooth gear; a cylindrical holder covering the outer circumference surface of the pivot member; a lock tooth having an external tooth gear arranged to be engaged with the internal tooth gear; and a cam arranged to push the lock tooth to engage or disengage the external tooth gear with or from the internal tooth gear; the pivot member including a bearing inner circumference surface located on the circular recessed portion, on the base member's side of the internal tooth gear in the axial direction, the base member including a circular support outer circumference surface on which the bearing inner circumference surface is slid, and the bearing inner circumference surface and the support outer circumference surface being arranged to position the pivot member relative to the base member in the radial direction.