It is an object of the present invention to provide an assistance device that can further reduce the burden on the person being assisted in assisting the sitting operation. In the operation processing of the seating operation by the assistance device (1), the elevating part (30) is lowered, and the upper body of the person (M) supported by the support member (50) is lowered from the initial standing posture. After the lowering step and the lowering step of the intermediate posture, the swinging portion (40) is rotated backward so that the support member (50) is retracted, and the central axis ( A step of raising the elevating part (30) so as to eliminate the downward movement amount of the support member (50) relative to A) and changing the person being assisted (M) from the intermediate position to the sitting position is included.着座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）による着座動作の動作処理には、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）を初期の立位姿勢から上半身が下降した中間姿勢とする下降工程と、下降工程の後に、支持部材（５０）が後退するように、揺動部（４０）を後旋回させるとともに、揺動部（４０）の後旋回に伴う中心軸（Ａ）に対する支持部材（５０）の下方移動量を消すように昇降部（３０）を上昇させて、被介助者（Ｍ）を中間姿勢から座位姿勢とする後退工程と、が含まれる。
