K. V. Mahadevan is a South Indian music composer.

K. V. Mahadevan, or "mAmA" as he was popularly known among his colleagues, has a special place in South Indian film music. He started his career as a happy composer with 'Anandhan' in 1942, contributed immensely for nearly half a century, before surrendering in 1990 with 'muruganE thuNai'. During this period he scored music for about 250 Tamil films. The special features of his compositions were: giving primary importance to lyrics and composing music that is perfectly suited to lyrics; always keeping a base in the Carnatic music systems; and giving independence to singers and other assistants to freely contribute ideas for improving his compositions. Some of the famous tamil movies for which he composed include 'adimai peN','thiruviLayaadal','vaanampaadi','thillaana mOganaambaaL','kandhan karuNai','muthalaaLi'. His most famous and recent composition in Telugu was in the movie directed by K.Vishwanath, 'Shankarabharanam' (1980).