An electronic device, comprising: a housing including a conductive portion forming at least a portion of a side surface; an antenna module disposed in an inner space of the housing and comprising: a printed circuit board, PCB, disposed in the inner space, including a first surface and a second surface facing a direction opposite to the first surface; at least one antenna element disposed on the first surface of the PCB or near the first surface in the PCB; a wireless communication circuit disposed on the second surface and configured to transmit and/or receive a radio signal through the at least one antenna element; and a protective member disposed on the second surface of the PCB and configured to at least partially surround the wireless communication circuit; and a conductive shielding layer formed of a conductive material coated on a surface of the protective member; and a conductive member comprising a support part and an extension part extended from the support part, wherein the support part is configured to support the antenna module, wherein the extension part is configured to fix the antenna module to the conductive portion, wherein at least a portion of the conductive member is disposed to face the conductive shielding layer of the antenna module, and wherein at least a portion of the conductive member is disposed to face the conductive portion; wherein the antenna module supported by the conductive member is disposed in an inner space of the housing such that the first surface of the PCB faces in a direction toward the side surface of the housing, and wherein the conductive member is configured to transfer heat generated by the antenna module to the conductive portion of the housing. a housing including a conductive portion forming at least a portion of a side surface; an antenna module disposed in an inner space of the housing and comprising: a printed circuit board, PCB, disposed in the inner space, including a first surface and a second surface facing a direction opposite to the first surface; at least one antenna element disposed on the first surface of the PCB or near the first surface in the PCB; a wireless communication circuit disposed on the second surface and configured to transmit and/or receive a radio signal through the at least one antenna element; and a protective member disposed on the second surface of the PCB and configured to at least partially surround the wireless communication circuit; and a conductive shielding layer formed of a conductive material coated on a surface of the protective member; and a printed circuit board, PCB, disposed in the inner space, including a first surface and a second surface facing a direction opposite to the first surface; at least one antenna element disposed on the first surface of the PCB or near the first surface in the PCB; a wireless communication circuit disposed on the second surface and configured to transmit and/or receive a radio signal through the at least one antenna element; and a protective member disposed on the second surface of the PCB and configured to at least partially surround the wireless communication circuit; and a conductive shielding layer formed of a conductive material coated on a surface of the protective member; and a conductive member comprising a support part and an extension part extended from the support part, wherein the support part is configured to support the antenna module, wherein the extension part is configured to fix the antenna module to the conductive portion, wherein at least a portion of the conductive member is disposed to face the conductive shielding layer of the antenna module, and wherein at least a portion of the conductive member is disposed to face the conductive portion; wherein the antenna module supported by the conductive member is disposed in an inner space of the housing such that the first surface of the PCB faces in a direction toward the side surface of the housing, and wherein the conductive member is configured to transfer heat generated by the antenna module to the conductive portion of the housing.