A terminal connection structure comprises a first terminal made in a plate shape and formed with a through-opening, a supporting section supporting the first terminal, a second terminal made in a plate shape and to be a connection counterpart of the first terminal, and a clip made of a plate-like material having an electrical conductivity, and having a central piece formed into a U-shape and opposed pieces continued from the central piece, the central piece being provided with a pair of projection portions projected from both side portions of the central piece to prevent the clip from excessively entering into the through-opening. The first terminal is interposed between the opposed pieces facing to each other with the central piece inserted into the through-opening, and the second terminal is inserted between a surface of the first terminal facing the pair of projection portions and the clip.