A circuit board unit, comprising: a printed circuit board; and a first connection member attached to the printed circuit board and connecting a circuit element of an electrical circuit including the printed circuit board and an electrical wire together, wherein the first connection member includes a terminal connection part directly connected to a terminal pin of the circuit element, and a wire connection part connected to the electrical wire, the wire connection part has a seat plate, and a leg part downwardly extending from the seat plate, a lower end part of the leg part being fixed to the printed circuit board, the terminal connection part is formed in a plate shape extending from the wire connection part in parallel to the printed circuit board and has a pin connection part connected to the terminal pin, a hole formed in the printed circuit board and having an orthographic projection area at least larger than that of the pin connection part of the terminal connection part as viewed in plane, and the terminal connection part of the first connection member is configured such that at least the pin connection part is positioned below or above the hole of the printed circuit board, characterized in that the hole corresponds to the terminal connection part and has such a planar area that a clearance δ is defined between an inner circumferential surface of the hole and an outer circumferential surface of the pin connection part of the terminal connection part as viewed in the plane, wherein a dimension of a clearance between the terminal connection part and the printed circuit board is set to a predetermined dimension. a printed circuit board; and a first connection member attached to the printed circuit board and connecting a circuit element of an electrical circuit including the printed circuit board and an electrical wire together, wherein the first connection member includes a terminal connection part directly connected to a terminal pin of the circuit element, and a wire connection part connected to the electrical wire, the wire connection part has a seat plate, and a leg part downwardly extending from the seat plate, a lower end part of the leg part being fixed to the printed circuit board, the terminal connection part is formed in a plate shape extending from the wire connection part in parallel to the printed circuit board and has a pin connection part connected to the terminal pin, a hole formed in the printed circuit board and having an orthographic projection area at least larger than that of the pin connection part of the terminal connection part as viewed in plane, and the terminal connection part of the first connection member is configured such that at least the pin connection part is positioned below or above the hole of the printed circuit board, characterized in that the hole corresponds to the terminal connection part and has such a planar area that a clearance δ is defined between an inner circumferential surface of the hole and an outer circumferential surface of the pin connection part of the terminal connection part as viewed in the plane, wherein a dimension of a clearance between the terminal connection part and the printed circuit board is set to a predetermined dimension.