Provided is a circuit assembly including: a circuit board; a bus bar having a top face fixed to a bottom face of the circuit board; an electronic component disposed on a top face of the bus bar; a heat dissipation member disposed on a bottom face of the bus bar; a heat transfer member interposed between the bus bar and the heat dissipation member, to transfer heat of the bus bar to the heat dissipation member; and a screw extending through a stack of the circuit board and the bus bar, the screw screwed to the heat dissipation member, fixing the stack to the heat dissipation member; and a spacer interposed between the circuit board and the heat dissipation member, the spacer surrounding at least a portion of an outer circumference of a shaft portion of the screw, and maintaining a thickness of the heat transfer member substantially uniform.