According to an embodiment, an electronic device comprises a housing comprising a first plate and a second plate facing away from to the first plate; and a substrate disposed between the first plate and the second plate and comprising a first side facing the first plate and a second side facing the second plate, wherein the substrate comprises, a first conductive plate disposed on a first insulating layers and facing the second side; a conductive pattern disposed on a second insulating layer, wherein the second conductive layer is between the first conductive layer and the first side; a second conductive plate disposed on a third insulating layer between the second insulating layer and the first side, and when the second plate is viewed from above the second side, the second plate at least partially overlaps with the first conductive plate; a ground plate disposed on a fourth insulating layer, wherein the fourth insulating layer is between the third insulating layer and the first side; a conductive via constructed through the third and fourth insulating layers, and electrically connected with the conductive pattern; and a wireless communication circuit electrically connected with the conductive via, and configured to transmit/receive at least one signal having a frequency band in the range of 20 GHz to 100 GHz.