To provide a pressing operation type input device, which is manufactured at low cost, and easily maintains high reliability over a long period of time with minimized design flexibility.

A magnetic sensor 2 with a built-in GMR element is mounted on a circuit board 1, and an operation key 4 is disposed within each of a plurality of openings 3a of an operation panel 3 covering the circuit board 1 so as to be movable upward and downward, each operation key 4 being biased to an upper initial position by a return spring 6. The operation key 4 includes a projection 4b protruding downward, and a magnet 5 is fixed to the lower surface of the projection 4b. Each magnet 5 is located above a detection area E of the magnetic sensor 2 in a non-operation state of the operation key 4, and when an optional operation key 4 is pressed down, the magnet 5 fixed to this operation key 4 intrudes into the detection area E, whereby the pressed operation key 4 is detected based on an output value of the magnetic sensor 2.