An electronic device includes first printed circuit board (PCB) structure including first layer including first conductive strip, second conductive strip electrically separated from first conductive strip and extending at least partially in parallel with first conductive strip, and third conductive strip electrically separated from first conductive strip and extending at least partially in parallel with first conductive strip, such that first conductive strip is between second conductive strip and third conductive strip, and second layer including first conductive layer, first insulating layer interposed between and in contact with first region of first layer and first region of second layer facing first region of first layer, second insulating layer interposed between second region of first layer abutting first region of first layer and second region of second layer abutting first region of second layer while contacting first layer, and third insulating layer interposed between second insulating layer and second region of second layer, while contacting second layer, and being separated from second insulating layer by air gap, and a wireless communication circuit electrically connected to first conductive strip and configured to transmit and/or receive radio frequency (RF) signal.