An electronic device (200, 300) comprising: a housing including: a first cover (220, 320) having a display area formed therein; a second cover (180, 280, 391) configured to face the first cover and formed of a composition containing a first ceramic material; a side frame (140, 240, 392) configured to surround a space between the first cover and the second cover; a circuit board (250, 350) disposed in the housing, the circuit board having a communication module (264, 266) disposed on a surface of the circuit board configured to transmit and receive radio waves; and a ceramic layer containing a second ceramic material that is formed as a ceramic film and is disposed between the circuit board and the second cover to cover the communication module, wherein a radiation area through which the radio waves pass includes at least part of the second cover and at least part of the ceramic layer; wherein the ceramic layer is configured to adjust changed characteristics of radio waves passing through the housing to a preferred range, wherein the communication module includes a first communication module and a second communication module, wherein the ceramic film includes a first film disposed between the first communication module and the second cover of the housing and a second film disposed between the second communication module and the second cover of the housing, and wherein the first film has a different permittivity from the second film, and each permittivity is adapted by varying the thickness of the first film and the second film depending on wireless communication performance required for the first communication module and the second communication module, respectively, wherein the circuit board includes a main circuit board having one or more electrical elements disposed thereon and an antenna board having the communication module disposed thereon, and wherein the antenna board is formed on at least part of a periphery of an inner surface of the housing, wherein a radiating surface of the communication module includes the antenna board disposed to face the second cover, the antenna board having a conductive pattern formed thereon. a housing including: a first cover (220, 320) having a display area formed therein; a second cover (180, 280, 391) configured to face the first cover and formed of a composition containing a first ceramic material; a side frame (140, 240, 392) configured to surround a space between the first cover and the second cover; a first cover (220, 320) having a display area formed therein; a second cover (180, 280, 391) configured to face the first cover and formed of a composition containing a first ceramic material; a side frame (140, 240, 392) configured to surround a space between the first cover and the second cover; a circuit board (250, 350) disposed in the housing, the circuit board having a communication module (264, 266) disposed on a surface of the circuit board configured to transmit and receive radio waves; and a ceramic layer containing a second ceramic material that is formed as a ceramic film and is disposed between the circuit board and the second cover to cover the communication module, wherein a radiation area through which the radio waves pass includes at least part of the second cover and at least part of the ceramic layer; wherein the ceramic layer is configured to adjust changed characteristics of radio waves passing through the housing to a preferred range, wherein the communication module includes a first communication module and a second communication module, wherein the ceramic film includes a first film disposed between the first communication module and the second cover of the housing and a second film disposed between the second communication module and the second cover of the housing, and wherein the first film has a different permittivity from the second film, and each permittivity is adapted by varying the thickness of the first film and the second film depending on wireless communication performance required for the first communication module and the second communication module, respectively, wherein the circuit board includes a main circuit board having one or more electrical elements disposed thereon and an antenna board having the communication module disposed thereon, and wherein the antenna board is formed on at least part of a periphery of an inner surface of the housing, wherein a radiating surface of the communication module includes the antenna board disposed to face the second cover, the antenna board having a conductive pattern formed thereon.