The present invention provides a bio-electrode composition capable of forming a living body contact layer for a bio-electrode that is excellent in conductivity and biocompatibility, is light-weight, can be manufactured at low cost, and can control significant reduction in conductivity even though the bio-electrode is soaked in water or dried. The present invention is accomplished by a bio-electrode composition including an (A) ionic material and a (B) resin other than the component (A), in which the component (A) has both a repeating unit “a” of a lithium salt, a sodium salt, a potassium salt, or an ammonium salt of sulfonamide including a partial structure represented by the following general formula (1) and a repeating unit “b” having a silicon atom, -R1-C(=O)-N--SO2-Rf1M+(1).本發明之課題係提供一種生物體電極組成物，可形成導電性及生物相容性(bioco mpatibility)優良，輕量，且能以低成本製造，無論被水潤濕抑或乾燥導電性也不會大幅降低之生物體電極用之生物體接觸層。 該課題之解決方法係一種生物體電極組成物，含有(A)離子性材料、及(B)該(A)成分以外的樹脂，該(A)成分具有下列兩者：具有下述通式(1)表示的部分結構之磺醯胺的鋰鹽、鈉鹽、鉀鹽、銨鹽之重複單元a；及具有矽之重複單元b。 -R1-C(=O)-N--SO2-Rf1M+(1)
