To provide an inexpensive graphite powder which has high capacity, small irreversible capacity, and small reactivity with electrolyte, and is suitable to be used as a material for a negative terminal of the secondary lithium ion battery.

The surface of an inexpensive natural graphite powder is adhered with a water-soluble polymer material (preferably a carboxymethylcellulose salt), and heat-treated to heat decompose the water-soluble polymer material to imperfectly carbonize in order to have the graphite powder supported with a carbon precursor composed of heat-decomposition product of the water-soluble polymer material. The graphite powder having an average particle diameter of at most 30 μm is obtained.

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