PROBLEM TO BE SOLVED: To provide a muscle contraction detection sensor for improving the accuracy of detecting muscle contraction. SOLUTION: A muscle contraction detection sensor for detecting muscle contraction is a substrate and a first pressing member pressed toward the muscle, and a first fluid arranged on an upper plate portion facing the muscle of the substrate. A first pressing member and a second fluid storage unit composed of a storage unit and a second fluid storage unit arranged at a position other than the upper plate portion and connected to the first fluid storage unit by a flow path. A first pressure detecting unit that has a contact surface of the above and detects a first pressure applied to the contact surface from the second fluid storage unit, and a second pressing member that is pressed toward a muscle and is a first pressing member. A second pressing member having different protrusion heights from the upper plate portion of the substrate in a no-load state and a second pressure detecting unit for detecting a second pressure applied from the second pressing member are provided. Detects muscle contraction based on changes in pressure and second pressure difference or ratio. [Selection diagram] Fig. 1【課題】筋肉の収縮を検出する精度を向上させる、筋収縮検出センサを提供する。【解決手段】筋肉の収縮を検出する筋収縮検出センサは、基板と、筋肉に向けて押し付けられる第１押付け部材であって、基板の筋肉と対向する上板部上に配置された第１流体格納部と、上板部上以外の位置に配置され、第１流体格納部と流路で連結された第２流体格納部とで構成される、第１押付け部材と、第２流体格納部との接触面を有し、第２流体格納部から接触面に加えられる第１圧力を検出する、第１圧力検出部と、筋肉に向けて押し付けられる第２押付け部材であって、第１押付け部材と無負荷状態における基板の上板部上からの突出高さが異なる、第２押付け部材と、第２押付け部材から加えられる第２圧力を検出する第２圧力検出部と、を備え、第１圧力及び第２圧力の差又は比の変化に基づいて筋肉の収縮を検出する。【選択図】図１
