Arnold Ap (July 1, 1945 – April 26, 1984) was a West Papuan cultural leader, anthropologist and musician. Arnold was the leader of the group Mambesak, and Curator of the Cenderawasih University Museum. He also broadcast Papuan culture on his weekly radio show.
His prominent study and performance of Papuan culture and music was seen by many as a challenge to the efforts of the Indonesian government against Papuan nationalism and identity. At the time of Ap's death, strong attempts were being made to unify Indonesian peoples under a more Javanese culture.
In November 1983 he was arrested by the Indonesian military special forces Kopassus and imprisoned and tortured for suspected sympathies with the Free Papua Movement, although no charges were laid. In April 1984 he was killed by a gunshot to his back. Official accounts claim he was trying to escape. Many supporters believe Ap was executed by Kopassus.
Another musician, Eddie Mofu, was also killed.