A walking assistant harness (2) attached to a leg of a trainee so as to assist walking of the trainee includes: a thigh frame (40) placed along a front side or a rear side of a thigh of the trainee; and a thigh fixation belt (30) connected to the thigh frame (40) at a connection portion, so as to fix the thigh of the trainee to the thigh frame (40), and the connection portion includes a connecting position adjustment mechanism configured to adjust a connecting position with the thigh fixation belt (30) in a right-left direction of the trainee.