Abstract: Provided are Composite graphite particles comprising core material comprising graphite obtained by heat treating petroleum based coke with a grindability index of 35 to 60 at a temperature of not less than 2500° C. and not more than 3500° C. and carbonaceous layer present on the surface of the core material, wherein the composite graphite particles have an intensity ratio ID/IG of 0.1 or more in intensity (ID) of peak in the range between 1300 and 1400 cm?1 and intensity (IG) of peak in the range between 1500 and 1620 cm?1 as measured by Raman spectroscopy spectrum, the composite graphite particles have a 50% particle diameter (D50) of not less than 3 ?m and not more than 30 ?m in accumulated particle size distribution by volume as measured by the laser diffraction method, and the composite graphite particles have a ratio I110/I004 of 0.