To provide a single heat transferring material which has a superior heat radiating characteristic and an ultra light weight and can contain a cooling liquid, such as the water, etc., and a heat radiating material, etc.

The base material of a heat transferring material and a heat radiating material is composed mainly of a three-dimensionally communicative porous material of alumina or an alumina alloy, at least partially contains alumina whickers, and has a specific gravity of 0.81-2.43 g/cm3. A heat radiating material preferably has a heat radiation factor of ≥0.62 and a specific gravity of 1.08-1.75 g/cm3, contains a liquid refrigerant in its base material, and the like.