An electronic device including an antenna device is provided. The electronic device includes a case member, a frame disposed around a periphery of one surface of the case member, forming sidewalls, and an antenna device for transmitting and receiving wireless signals. The antenna device includes a first radiation conductor forming a first part of the frame, a second radiation conductor disposed in a vicinity of the first radiation conductor, forming a second part of the frame, a third radiation conductor provided on the case member and connected to a first power supply of the electronic device, together with the first radiation conductor, and a fourth radiation conductor provided on the case member and connected to a ground of the electronic device. At least a part of the fourth radiation conductor is disposed in a vicinity of the second radiation conductor.