An electronic circuit device includes a bus bar, a base component and an electronic component. The bus bar has an external connector terminal capable of receiving electric power from an external power source. The base component has a metallic heat radiation portion and is disposed to oppose the bus bar. The electronic component is held between the bus bar and heat the radiation portion of the base component. The bus bar further includes fixing terminals extending toward the base component. The fixing terminals are fixed to the base component to constitute fixing portions. The fixing portions are configured to have elasticity and exert a restoring force such that a distance between the bus bar and the base component reduces. The electronic component is in pressure contact with the bus bar and the base component by the restoration force of the elasticity of the fixing portions.