NOVELTY - A silicone composition contains 100 parts mass organopolysiloxane (A) (I) containing alkenyl group coupled with silicon atom(s), organo-hydrogen-polysiloxane (B) containing hydrogen atom coupled with silicon atom(s), 0.1-10 parts mass organic compound (C) which does not contain silicon atom, and containing more than two acrylol group and/or methacryloyl groups, and addition reaction catalyst (D). Amount of hydrogen atoms coupled with silicon atom in component (A) is 0.4-0.5 mol times with respect to 1 mole of silicon atom-bonded alkenyl groups in component (A).    USE - Silicone composition is used for solar cell module (claimed) for single crystal silicon solar cell, polycrystalline-silicon solar cell, spherical silicone solar cell, amorphous-silicon solar cell, hetero joint solar cell, cadmium-telluride solar cell, dye-sensitized solar cell, and organic-semiconductor solar cell.    ADVANTAGE - The silicone composition has high transparency.    DETAILED DESCRIPTION - A silicone composition contains 100 parts mass organopolysiloxane (A) of formula: RaR'bSiO(4-a-b)/2 (I) containing alkenyl group coupled with at least two silicon atoms in a molecule, organo-hydrogen-polysiloxane (B) containing hydrogen atom coupled with at least two silicon atoms in a molecule, 0.1-10 parts mass organic compound which does not contain silicon atom, and containing more than two acrylol group and/or methacryloyl groups in a molecule, and catalytic amount of addition reaction catalyst. The amount of hydrogen atoms coupled with silicon atom in component (A) is 0.4-0.5 mole times with respect to one mole of silicon atom-bonded alkenyl groups in component (A).    R=alkenyl;    R'=optionally substituted 1-10C monovalent hydrocarbyl which does not contains aliphatic unsaturated bond;    a=more than 0 to 2;    b=more than 0 and less than 3;and    a+b=more than 0 to 3.    An INDEPENDENT CLAIM is included for solar cell module, which is formed by connecting solar cell sealed by hardened material of silicone composition.