Biological electrode

A biological electrode comprising,

• a support member,
• an electrode member made of a conductive rubber having a supported portion supported by the support member and a plurality of electrode portions provided so as to protrude from the supported portion on the opposite side to the support member and bring into contact with a body of a subject,
• a connector that electrically connects the electrode member to the outside and is configured such that a part thereof is embedded in the supported portion of the electrode member and extends through the support member to have a connecting portion to the outside which is positioned on a surface of the support member on the opposite side to the electrode member,
• wherein
• the plurality of electrode portions are arranged circularly or concentrically on an electrode portion forming surface of the supported portion, and
• each of the plurality of electrode portions is formed so that a cross-sectional area thereof gradually decreases from a proximal end portion thereof toward a distal end portion thereof and a center of a cross section of the distal end portion is positioned radially outward of a center of a cross section of the proximal end portion as viewed from an arrangement center of the plurality of electrode portions.