To provide an underground heat exchange component made of steel by means of heat absorption or heat dissipation which realizes the heat exchange in the underground and the heat exchange in the wide underground which has been impossible heretofore by allowing a heat exchange component made of steel using ferritic steel to withstand high temperature exceeding 700C.

The underground heat exchange component made of steel is composed of high chromium ferritic heat resistant steel containing, by weight%, 110-3 to 110-1% C, 13 to 30% Cr, 110-3 to 110-1% N and Ni10(C+N), having a structure where a ferritic phase occupies by 70 vol.%, and strengthened by the precipitation of one or more kinds selected from intermetallic compounds, carbides and nitrides.