An antenna device includes: a substrate including a base layer, a first layer disposed on one surface of the base layer, a second layer disposed on another surface of the base layer, at least one first coil pattern disposed on the first layer, and at least one second coil pattern disposed on the second layer; and a magnetic body. A first region of the substrate is disposed on one surface of the magnetic body, and a second region of the substrate is disposed on another surface of the magnetic body. The at least one first coil pattern and the at least one second coil pattern are connected to each other to form an antenna coil having a solenoid shape disposed around the magnetic body.