To provide the fixing structure of the sheet metal member which can avoid the fall of the fixed strength of a superposed part, while enabling to prevent the generation of a rust in the superposed part of the bottom of the box-like first sheet metal member and the second sheet metal member and can improve the appearance quality of the superposed part.

The bottom 10T of the box-like first sheet metal member 10 laps over the second sheet metal member 6 and a plurality of fix parts 20 of the first sheet metal member 10 are fixed to a plurality of fixed parts 30 of the second sheet metal member 6 respectively, and the gap S is formed between the first sheet metal member part 55 other than a plurality of fix parts 20 and the second sheet metal member part 56 other than a plurality of fixed parts 30. The annular sealer 40, which surrounds a plurality of fix parts 20 and a plurality of fixed parts 30, is applied between the bottom 10T of the first sheet metal member 10 and the second sheet metal member 6, and the drainage part, which discharges the water in the area surrounded by the toroidal sealer 40 to outside of area, is formed.