<P>PROBLEM TO BE SOLVED: To provide a sulfate damage prevention method and a sulfate damage prevention structure by which the damage caused by sulfate can be easily prevented even when the production of sulfate deeply exerts on the underground or it is a land where sulfate is produced originally. ??<P>SOLUTION: In the ground surface 1a of a land 1 in which sulfate is generated or sulfate shall be generated, while soil 3 with sulfate generated or to be generated with sulfate is left below, a water retaining soil layer 4 having high water retaining performance higher than that of the soil 3 of the land 1 is formed. ??<P>COPYRIGHT: (C)2010,JPO&INPIT ??