Provided is a circuit structure using a printed-circuit board with a novel structure that can provide a plurality of types of circuit specifications by switching connection of circuit patterns, allows circuit specifications to be easily identified, and achieves excellent connection workability and connection stability for circuit patterns. The circuit structure includes: a printed-circuit board 18 on which a plurality of circuit patterns are provided; and a circuit switching component, wherein the circuit switching component includes bus bar support bases on which any connection bus bars selected can be mounted and held, the plurality of types of connection bus bars are classified according to the number and the position of lead portions to be electrically connected to connection points, and a plurality of types of circuit specifications are provided by changing a mounting mode of the connection bus bars to the bus bar support bases.