It is an object of the present invention to provide an assistance device that can further reduce the burden on the person being assisted during standing-up assistance. In the operation process of the standing-up operation by the assistance device (1), the swinging portion (40) is swung forward and the swinging portion (40) is swung forward so that the support member (50) moves downward while moving forward. The elevating part (30) is lowered more than the upward movement amount Nu of the support member (50) with respect to the central axis (A), and the person (M) supported by the support member (50) is in the initial sitting position. A forward process in which the upper body is tilted forward from the posture is included, and a lift process in which the elevating unit (30) is raised to bring the person being assisted (M) from the intermediate position to the standing posture.起立動作の補助の際の被介助者の負担をより軽減することができる介助装置を提供することを目的とする。 介助装置（１）による起立動作の動作処理には、揺動部（４０）を前旋回させるとともに、支持部材（５０）が前進しながら下方へ移動するように揺動部（４０）の前旋回に伴う中心軸（Ａ）に対する支持部材（５０）の上方移動量Ｎｕよりも大きく昇降部（３０）を下降させて、支持部材（５０）に支持された被介助者（Ｍ）を初期の座位姿勢から上半身が前傾した中間姿勢とする前進工程と、昇降部（３０）を上昇させて、被介助者（Ｍ）を中間姿勢から立位姿勢とする上昇工程と、が含まれる。
