Angle sensor device has magnetic force detectors detecting alternation of magnetic force caused by rotation of a throttle gear. The magnetic force detectors are buried in a molded body of the angle sensor device constructed of foamed resin. The magnetic force detectors each has a sensing unit detecting alteration of magnetic force and a computing unit computing based on signals from the sensing unit and outputting signals depending on the alteration of magnetic force and is formed in L-shape. Two of the magnetic force detectors are placed opposite each other such that one of the sensing units is disposed on the other sensing unit. The molded body has a cavity surrounded by the magnetic force detectors.
