There are provided an antenna integrally formed with a case and a method of manufacturing the same. An antenna integrally formed with a case according to an aspect of the invention includes: a case unit forming an exterior of an electronic device, a radiator comprising a radiation unit tightly fixed to an outer surface of the case unit and terminal units each extending from an end portion of the radiation unit, passing through the case unit, and exposed on the inside of the case unit, and contact pins provided on a board disposed in an interior space of the case unit and electrically connected to the individual terminal units.