A thermally conductive sheet, which contains: a binder; carbon fibers; and an inorganic filler, wherein the thermally conductive sheet is to be sandwiched between a heat source and a heat dissipation member of a semiconductor device, wherein the carbon fibers have an average fiber length of 50 μm to 250 μm, wherein thermal resistance of the thermally conductive sheet is less than 0.17 K·cm2/W, as measured in accordance with ASTM-D5470 with a load of 7.5 kgf/cm2, and wherein the thermally conductive sheet has an average thickness of 500 μm or less.