The invention provides a rotation sensor which is capable of detecting the turning angle and the turning direction of a detection target such as a steering wheel accurately and in real time over a wide range. The rotation sensor comprises first and second rotation detection means for generating respective first and second detection signals having the same period and the different phase which repeat with a gradual increase and a gradual decrease concomitantly with rotation of a rotor, and a third rotation detection means for generating the third detection signal which repeats with a gradual increase and a gradual decrease concomitantly with rotation of the rotor, wherein the rough turning angle of the rotor is detected based on the third detection signal and the fine turning angle of the rotor is detected based on the first detection signal or the second detection signals.