Discussed is a PCB assembly and a manufacturing method of a PCB assembly in which at least two PCBs are electrically connected. The PCB assembly includes a connection metal pin having a body and legs, the body having electric conductivity, and having a pin shape elongated in one direction, a portion of the body being bent according to a predetermined angle of the at least two PCBs arranged in a rotated state, portions of the legs being bent and respectively extended in another direction from opposite ends of the body, the bent and extended portions of the legs being inserted through connection holes respectively formed in the at least two PCBs, and bent and extended terminals of the legs respectively being bent inward to be tightly fixed to lower surfaces of the at least two PCBs.