Electronic device having metal case and metal case used for same

The present invention relates to an electronic device having a metal case, the electronic device comprising: a metal case having at least one electronic circuit or antenna formed therein; a metal pad arranged at the metal case and electrically connected to the at least one electronic circuit or antenna; a metal sheet attached to one surface of the metal pad; and an electronic circuit board electrically connected to the at least one electronic circuit or antenna of the metal case through a metal instrument for connection which detachably contacts the metal sheet.