An apparatus for manufacturing a lithium-ion secondary cell negative-electrode carbon material by heat-treating carbon particles while causing the carbon particles to flow within a heat-treatment furnace, the apparatus having a heat-treatment furnace provided with a carbon-particle supply opening for supplying the carbon particles into the interior, and a negative-electrode carbon material recovery opening for taking out the negative-electrode carbon material from the interior and a cooling tank connected in an airtight manner to the negative-electrode carbon material recovery opening of the heat-treatment furnace, and provided with a cooling means.