To provide a thermally conductive polymeric composition which has excellent thermal conductivity and is suitable for heat-dissipating members, heat transfer members or materials for constituting them in electronic equipment and the like, and a thermal conduction molded product.

The graphitized carbon fiber to be incorporated into a thermally conductive polymeric composition has a spacing (d002) of graphite layers, measured by the X-ray diffraction method, of <0.3370 nm and, at the same time, a peak intensity ratio (P101/P100) of the (101) diffraction peak (101) to the (100) diffraction peak of ≥1.15. This graphitized carbon fiber can be obtained by conducting each treatment of spinning with the use of a mesophase pitch as the raw material, rendering the resulting fiber infusible, and carbonization in the order named, then effecting pulverization and subsequent graphitization, and has a fiber diameter of 5-20 μm and an average particle diameter of 5-500 μm. The thermally conductive polymeric molded product can be obtained by molding the thermally conductive polymeric composition into a specified shape.