A differential transformer type magnetic sensor includes a first coil layer, a second coil layer, and an insulating layer formed between the first coil layer and the second coil layer. The first coil layer includes a detection coil and a first drive coil. The second coil layer includes a reference coil and a second drive coil. The first drive coil and the second drive coil are electrically connected together so that a direction of drive current flowing in the first drive coil is the same as a direction of drive current flowing in the second drive coil. The detection coil and the reference coil are electrically connected together so that a direction of induced current flowing in the detection coil is reverse to a direction of induced current flowing in the reference coil.