To provide a deterioration prediction mapping device and a deterioration prediction mapping method that efficiently and precisely predict a corrosion speed of a steel tower.

Multiple regression analysis means 10 includes: explanation variable input means 11 of inputting an explanation variable as a variable affecting a target variable; relational expression structuring means 12 of structuring a relational expression of the explanation variable and corrosion speed; selection variable relational expression selection means 13 of selecting a relational expression with the best evaluation among relational expressions structured while one of explanation variables is excluded; non-selection variable relational expression selection means 14 of selecting a relational expression with the best evaluation among relational expressions structured while one of explanation variables which are not input is added; relational expression selection means 15 of selecting a relational expression with high evaluation between the selection variable relational expression selection means 13 and the non-selection variable relational expression selection means 14; and relational expression verification means 16 of verifying which evaluation is higher between the selected relational expressions and the relational expressions structured by the relational expression structuring means 12.