A fixation structure includes an electrical wire, a board, and a stapler. The electrical wire includes a core wire and a cover member. The electrical wire includes a core-wire covered part covered by the cover member, and a core-wire exposed part exposed from the core-wire covered part. The board includes a junction part electrically connected with the core-wire exposed part. The stapler includes a contact part and a fixation part. The contact part has a plate shape, and is positioned at a boundary between the core-wire exposed part and the core-wire covered part while contacting the core-wire exposed part and the core-wire covered part from a side opposite to the board when the core-wire exposed part is connected with the junction part. A pair of the fixation parts are provided on both sides of the contact part and fix the contact part and the board.