The inventions are: a composition capable of forming a heat-dissipating member that has high thermal conductivity and in which the thermal expansion coefficient can be controlled; and a heat-dissipating member. This composition for a heat-dissipating member comprises a thermally conductive first inorganic filler bonded to one end of a first coupling agent, and a thermally conductive second inorganic filler bonded to one end of a second coupling agent, the composition being characterized in that: at least one of the first coupling agent and the second coupling agent is a liquid crystal silane coupling agent; the other end of the first coupling agent and the other end of the second coupling agent each have a functional group bondable with one another; and the other end of the first coupling agent bonds with the other end of the second coupling agent by a curing treatment.