S. Krishnamoorthy (born 9 October), better known by his screenname Madhan Bob, is a popular comedian and Tamil film actor from Chennai, Tamil Nadu, India. He started his film career as a musician and became an actor instead. Apart from appearing in supporting roles in Tamil films he also appears in the Sun TV comedy show "Asathapovathu Yaaru" as one of the judges. His debut film was "Vaaname Ellai". It was Madan Bob who first taught "Maragathamani" music.