Provided are an input device capable of a variety of operations with a simple configuration, and an electronic apparatus using the same. A rotary operation portion 2 includes ring magnets 4 securely attached at opposite ends of a roller 3, each ring magnet 4 being magnetized with the S- and N-poles alternating at a predetermined angular pitch, and magnetic sensing elements 13 and stationary magnets 7 disposed so as to face their respective ring magnets 4. The rotary operation portion 2 is covered by an operation plate 16 having formed at its center a roller insertion hole 16a for projecting a part of the outer circumferential surface of the roller 3. The rotation of the roller 3 is magnetically sensed, and switches 9 and 11 are provided so as to be turned “ON”/“OFF” in accordance with operations of pressing the roller 3 and rocking the operation plate 16 in the “front”, “back”, “left”, and “right” directions.