To easily and stably joint a plurality of leg parts of each fitting by using a robot, and to improve mounting accuracy by preventing displacement of a solid state imaging device due to contraction of a melting metal in the jointing, in a method of mounting a solid state imaging device.

Passages 3d for filling fusible metal are formed in a plurality of joint parts 3c of a second fitting 3; respective joint parts 2c, 3c are faced to each other to position the joint parts 3c of the second fitting 3 with the passages 3d for filling fusible metal formed therein above the joint parts 2c of a first fitting 2; and molten solder 21 is filled in spaces 6 between the respective joint parts 2c, 3c faced to each other through the passages 3d for filling fusible metal generally at the same time and solidified to joint the first fitting 2 to the second fitting 3.