In this study, an intermediate process for forcibly orienting carbon fibers was proposed in order to improve the thermal conductivity in thickness direction of a polymer composite sheet. Thin strands containing carbon fibers obtained by extrusion process were hot-pressed to produce an intermediate sample. After giving a zigzag shape to this intermediate sample, the target structure was obtained by folding the sample. Laser flash analysis of the thermal conductivity of sample showed that the value of 1.74 W / (m・K) was achieved at the carbon fiber volume fraction of 15%.