To provide a structure for connecting a main board with a flexible printed board which can improve strength for connecting the main board with the flexible printed board opposed to a stress of the main board from the outside direction, and can reduce a production cost.

First, a solder printing is carried out using a metal mask etc., a solder 10 is mounted on a land 4 of the main board 1, and a solder 11 is mounted on a land 5. Next, an FPC 2 is mounted on the main board 1 using a mounter so that the land 5 of the main board 1 and the through-hole 8 of the FPC 2 overlap each other, and a reinforcing material 9 is mounted on the FPC 2 to cover the through-hole 8. Next, the solder 10 and the solder 11 are melted using a reflow apparatus etc. and by hardening the solder 10 and the solder 11, the land 4 and a land 7 are connected through the solder 10, and the land 5 and the reinforcing material 9 are connected through the solder 11.