PROBLEM TO BE SOLVED: To provide an arm assist which can be firmly attached to an operator's body in a stable state, can support an upper arm at a height to be maintained, and can support the upper arm even when the upper arm is swung in the left-right direction. SOLUTION: A jacket 2 having a back body 11 and a front body 12 and having fastening belts 7a, 7b which can be freely tightened and fastened for fixing the back body 11 to an operator, and left and right of the back body 11, respectively. A support body 3 having a rod-shaped portion 8 disposed at the upper end and an extension portion 9 extending from the upper end portion thereof to the vicinity of the armpit of the worker, a surface fastener, and an arm receiving portion 10 for receiving the upper arm of the worker. The arm holding rod body 4 having a vertical direction, which is rotatable in the vertical direction, the end portion of the extending portion 9 which is the fixed side, and the end portion of the arm holding rod body 4 which is the vertical direction rotating side are located under the armpit. An arm assist 1 including a ratchet 5 that restricts downward rotation of the arm holding rod 4. [Selection diagram] Figure 1【課題】作業者の身体にしっかりと安定状態で取り付けることができ、維持したい高さで上腕を支持でき、左右方向に上腕を旋回させても上腕を支持できるアームアシストを提供する。【解決手段】後身頃１１と前身頃１２を有しかつ後身頃１１を作業者に固定するための締緩自在の締付ベルト７ａ、７ｂとを有する上着２と、後身頃１１の左右それぞれに配設される棒状部８を有しかつその上端部から作業者の脇の下近傍まで延出する延出部９を有する支持体３と、面ファスナーと、作業者の上腕を受ける腕受け部１０を有する、上下方向に回動可能な腕保持棒体４と、固定側となる延出部９の端部と上下方向回動側となる腕保持棒体４の脇の下側の端部とを連結させる、腕保持棒体４の下方向の回動を制限するラチェット５とを備えたアームアシスト１。【選択図】図１
