Disclosed is an embedded antenna of a wireless device that can be formed by pattern printing and a manufacturing method thereof. The embedded antenna of a wireless device according to the present invention comprises a substrate accommodated in the wireless device; a radiation unit printed on an inner surface of a housing of the wireless device and connected to the substrate, for transmitting and receiving electrical signals; and an insulation unit printed on the radiation unit, for insulating the radiation unit. Here, the radiation unit includes first and second radiators sequentially printed as a pattern on the inner surface of the housing, and the insulation unit includes first and second insulators printed to cover the first and second radiators in order. According to the configuration like this, since the radiation unit and the insulation unit can be formed to have a minimum thickness by pattern printing, the size of the embedded antenna embedded in the wireless device can be minimized.