An induction heating unit enabling to attaching coil on coil attaching surface of bobbin with a high degree of accuracy, and a fixing device capable of maintaining the distance between the coil and the member to be heated at a high degree of accuracy, ensuring uniformity of temperature distribution of the member to be heated, rising temperature at a high speed, and enhancing quality of fixation. In an induction heating unit 30 including a magnetizing coil 39 attached on a coil bobbin 38 which is disposed outside of annular body 19 to be heated, the unit including: a layer of elastic adhesive 44a provided on the outer surface of the coil bobbin 38; a magnetizing coil 39 provided on the layer of elastic adhesive 44a, the magnetizing coil 39 being wound beforehand following an attaching surface; and a layer of elastic adhesive 44b provided on the magnetizing coil 39.