A communication device, comprising: a main body case; a controller that is provided inside the main body case; a communication unit that is connected to the controller; an elongated antenna unit that is connected to the communication unit, and a measurement unit that is connected to the controller and is configured to measure biological information, a first substrate, a second substrate, and a third substrate that are disposed inside the main body case, a connector that links the first substrate and the second substrate, wherein the second substrate is disposed opposite the first substrate via the connector; wherein the connector is linked to the third substrate on which the antenna unit is disposed, the third substrate, on which the antenna unit is disposed, is disposed, bent in an arc shape along an inner wall surface of the main body case, on an outer peripheral portion of the first substrate and the second substrate and at a position corresponding to a gap between the second substrate and the first substrate, wherein the second substrate has a component substrate on which the controller is disposed, and a ground substrate on which a ground is disposed, wherein the component substrate and the ground substrate are linked by a linking unit, wherein the first substrate and the second substrate are disposed parallel to each other by folding around the connector, wherein the component substrate and the ground substrate are folded around the linking unit so that the ground substrate is disposed to overlap the component substrate and so that the ground substrate is disposed between the component substrate and the first substrate. a main body case; a controller that is provided inside the main body case; a communication unit that is connected to the controller; an elongated antenna unit that is connected to the communication unit, and a measurement unit that is connected to the controller and is configured to measure biological information, a first substrate, a second substrate, and a third substrate that are disposed inside the main body case, a connector that links the first substrate and the second substrate, wherein the second substrate is disposed opposite the first substrate via the connector; wherein the connector is linked to the third substrate on which the antenna unit is disposed, the third substrate, on which the antenna unit is disposed, is disposed, bent in an arc shape along an inner wall surface of the main body case, on an outer peripheral portion of the first substrate and the second substrate and at a position corresponding to a gap between the second substrate and the first substrate, wherein the second substrate has a component substrate on which the controller is disposed, and a ground substrate on which a ground is disposed, wherein the component substrate and the ground substrate are linked by a linking unit, wherein the first substrate and the second substrate are disposed parallel to each other by folding around the connector, wherein the component substrate and the ground substrate are folded around the linking unit so that the ground substrate is disposed to overlap the component substrate and so that the ground substrate is disposed between the component substrate and the first substrate.