NOVELTY - A negative-electrode composition contains negative-electrode active material, conductive support agent and binder. The negative electrode active material consists of composite particles including cobalt and tin, and has two or more pores which connect on surface of the composite particles in a cut surface. The negative-electrode composition has crystal phase with peak corresponding to (2( theta )) at 28.9 degrees , 32.8 degrees , 41.4 degrees , 42.6 degrees and 44.3 degrees in powder X-ray diffractometry. The conductive support agent is carbon material chosen from carbon nanofiber, acetylene black and Ketchen black.    USE - Composition is used for negative electrode for lithium-ion secondary battery (claimed) for mobile telephone, notebook computer and electric vehicle.    ADVANTAGE - The negative electrode formed using composition provides lithium-ion secondary battery with excellent cycling characteristics and high capacity.    DETAILED DESCRIPTION - A negative-electrode composition contains negative-electrode active material, conductive support agent and binder. The negative electrode active material consists of composite particles including cobalt and tin, and having structure in which cobalt is unevenly distributed in tin, and position focusing on tin, and has two or more pores which connect on surface of the composite particles in a cut surface. The ratio of cobalt with respect to the total amount of tin and cobalt is 5-40 atomic%. The cobalt is unevenly distributed in the outer surface of the composite particles, and inner surface of the pore. The negative-electrode composition has crystal phase with peak corresponding to (2( theta )) at 28.9 degrees , 32.8 degrees , 41.4 degrees , 42.6 degrees and 44.3 degrees , in powder X-ray diffractometry. The conductive support agent is carbon material chosen from carbon nanofiber, acetylene black and Ketchen black, and is adhered to outer surface of the composite particles and inner surface of the pore at mesh shape. An INDEPENDENT CLAIM is included for negative electrode of lithium-ion secondary battery.