NOVELTY - A silicon carbon composite cathode material is prepared by preparing silicon dispersion using 0-99.5 pts. wt. polymerizable unsaturated monomer and 0.5-100 pts. wt. crosslinking agent as grinding solvent, mixing 0.005-0.5 wt.% polymerization inhibitor, grinding, adding organic weak acid, sealing container with a stirrer under protection of inert gas, adding grinding solvent in ball mill, adding 1-15 wt.% coupling agent, stirring at 900-1500 rpm for 30 minutes to obtain silicon liquid, and adding grinding solvent, conductive carbon black and grinding solvent.    USE - Silicon carbon composite cathode material for preparing lithium ion battery.    ADVANTAGE - The silicon carbon composite cathode material provides lithium ion battery with high efficiency.    DETAILED DESCRIPTION - A silicon carbon composite cathode material is prepared by preparing silicon dispersion using 0-99.5 pts. wt. polymerizable unsaturated monomer and 0.5-100 pts. wt. crosslinking agent as grinding solvent, mixing 0.005-0.5 wt.% polymerization inhibitor, grinding, adding organic weak acid, sealing container with a stirrer under protection of inert gas, adding grinding solvent in ball mill, adding 1-15 wt.% coupling agent, stirring at 900-1500 rpm for 30 minutes to obtain silicon liquid. The resultant product is added with grinding solvent, followed by adding 0.5 wt.% conductive carbon black, 5 wt.% grinding solvent, 1-10 wt.% oil soluble initiator, and 0.1-2.0 wt.% chain transfer agent, stirring at 900-1500 rpm to form organic monomer/carbon black dispersion as dispersed phase, adding de-ionized water and 1-5.0 wt.% polyethylene alcohol, completely dissolving resultant product, adding and dissolving 0.01 wt.% sodium nitrite, stirring, emulsifying, adding emulsified dispersion solution into container equipped with reflux condenser tube, separating funnel, thermometer and nitrogen pipe reactor, stirring and raising the temperature to 80 degrees C, reacting for 30 minutes, heating to 90 degrees C, reacting for 6-10 hours to obtain polymer/silicon-carbon black composite micro-sphere emulsion, adding de-ionized water in graphite powder and stirring to obtain graphite dispersion, adding the polymer/carbon black composite micro-sphere emulsion, stirring, adjusting dispersion with solid content of 15-25 wt.% to obtain graphite/polymer microsphere composite of dispersion. The resultant product is subjected to spray drying, followed by hot processing, crushing, kneading under the protection of nitrogen at 250-350 degrees C, sintering, cooling naturally to room temperature, crushing and sieving to obtain carbon composite cathode material. An INDEPENDENT CLAIM is also included for a method for preparing a silicon carbon composite cathode material.