A bio-electrode composition comprising a composite comprising an ionic polymer material and particles, wherein the component comprises the particles bonded to the polymer comprising at least one repeating unit selected from the group consisting of repeating units-a1 to -a7 shown by the following general formula, wherein R 1, R 3, R 5, R 8, R 10, R 11, and R 13 each independently represent a hydrogen atom or a methyl group; R 2, R 4, R 6, R 9, R 12, and R 14 each independently represent any of a single bond, and a linear, branched, or cyclic hydrocarbon group having 1 to 13 carbon atoms optionally having either or both of an ester group and an ether group; R 7 represents a linear or branched alkylene group having 1 to 4 carbon atoms, and one or two hydrogen atoms in R 7 are optionally substituted with a fluorine atom; X 1, X 2, X 3, X 4, X 6, and X 7 each independently represent any of a single bond, a phenylene group, a naphthylene group, an ether group, an ester group, and an amide group; X 5 represents any of a single bond, an ether group, and an ester group; Y represents an oxygen atom or a -NR 19 - group; R 19 represents a hydrogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms and optionally bonded to R 4 to form a ring; "m" represents an integer of 1 to 4; a1, a2, a3, a4, a5, a6, and a7 satisfy 0≤a1≤1.0, 0≤a2≤1.0, 0≤a3≤1.0, 0≤a4≤1.0, 0≤a5≤1.0, 0≤a6≤1.0, 0≤a7≤1.0, and 0<a1+a2+a3+a4+a5+a6+a7≤1.0; M + represents an ion selected from the group consisting of an ammonium ion, a lithium ion, a sodium ion, a potassium ion, and a silver ion; and Rf 5, Rf 6, and Rf 7 each represent a fluorine atom, or a linear or branched alkyl group having 1 to 4 carbon atoms, and have at least one fluorine atom; the polymer comprising said repeating unit further having a repeating unit b having an alkoxysilyl group as shown by the following general formula, where R 20 represents a hydrogen atom or a methyl group; X 8 represents any of a single bond, a phenylene group, a naphthylene group, an ether group, an ester group, and an amide group; R 21 represents a single bond, a linear, branched, or cyclic alkylene group having 1 to 10 carbon atoms, or a phenylene group, and optionally contains an oxygen atom or a nitrogen atom; each R 22 is identical to or different from one another and represents an alkyl group having 1 to 4 carbon atoms; and "b" satisfies 0<b<1.0. a composite comprising an ionic polymer material and particles, wherein the component comprises the particles bonded to the polymer comprising at least one repeating unit selected from the group consisting of repeating units-a1 to -a7 shown by the following general formula, wherein R 1, R 3, R 5, R 8, R 10, R 11, and R 13 each independently represent a hydrogen atom or a methyl group; R 2, R 4, R 6, R 9, R 12, and R 14 each independently represent any of a single bond, and a linear, branched, or cyclic hydrocarbon group having 1 to 13 carbon atoms optionally having either or both of an ester group and an ether group; R 7 represents a linear or branched alkylene group having 1 to 4 carbon atoms, and one or two hydrogen atoms in R 7 are optionally substituted with a fluorine atom; X 1, X 2, X 3, X 4, X 6, and X 7 each independently represent any of a single bond, a phenylene group, a naphthylene group, an ether group, an ester group, and an amide group; X 5 represents any of a single bond, an ether group, and an ester group; Y represents an oxygen atom or a -NR 19 - group; R 19 represents a hydrogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms and optionally bonded to R 4 to form a ring; "m" represents an integer of 1 to 4; a1, a2, a3, a4, a5, a6, and a7 satisfy 0≤a1≤1.0, 0≤a2≤1.0, 0≤a3≤1.0, 0≤a4≤1.0, 0≤a5≤1.0, 0≤a6≤1.0, 0≤a7≤1.0, and 0<a1+a2+a3+a4+a5+a6+a7≤1.0; M + represents an ion selected from the group consisting of an ammonium ion, a lithium ion, a sodium ion, a potassium ion, and a silver ion; and Rf 5, Rf 6, and Rf 7 each represent a fluorine atom, or a linear or branched alkyl group having 1 to 4 carbon atoms, and have at least one fluorine atom; the polymer comprising said repeating unit further having a repeating unit b having an alkoxysilyl group as shown by the following general formula, where R 20 represents a hydrogen atom or a methyl group; X 8 represents any of a single bond, a phenylene group, a naphthylene group, an ether group, an ester group, and an amide group; R 21 represents a single bond, a linear, branched, or cyclic alkylene group having 1 to 10 carbon atoms, or a phenylene group, and optionally contains an oxygen atom or a nitrogen atom; each R 22 is identical to or different from one another and represents an alkyl group having 1 to 4 carbon atoms; and "b" satisfies 0<b<1.0.