To provide parts for structure suitable for a structure exposed to very high heat flux and capable of displaying structural functions.

Parts for structure includes pieces 10, 12 of a heat structural composite material coupled with a metal wall 14 provided with a fluid circulating passage 16, the pieces includes plates 10 and a plurality of stiffeners 12 formed integrally with the plates 10 and arranged on one side of each plate 10 with space apart from each other and the metal wall 14 is mounted on tip edge parts of the stiffeners 12. The plates 10 exposed to heat flux are made to radiate heat toward the metal wall 14 via gaps 20 between the plates 10 and the stiffeners 12.