A heat storage/dissipation material has a constitution in which heat storage/dissipation titanium oxide made of Ti3O5 is dispersed in heat transfer oil in a liquid form, the heat storage/dissipation titanium oxide not undergoing phase transition into a β-phase that has properties of a non-magnetic semiconductor and maintaining a state of a paramagnetic metal as long as the heat storage/dissipation titanium oxide is not subjected to pressure or light for heat dissipation. The heat storage/dissipation material is capable of maintaining a state of storing heat as long as the heat storage/dissipation material is not subjected to the pressure or the light for heat dissipation and is capable of releasing heat when subjected to the pressure or the light for heat dissipation, and therefore is capable of releasing the stored heat at a desired timing.