Long-tailed macaques (Macaca fascicularis) are widely distributed animals around the world that require special attention from the research and management perspectives. Daily activity budget of M. fascicularis were studied near the Kuala Selangor Nature Park as one part of study on its behavior and ecology. The study location was based along the M. fascicularis trails starting from the ticket counter of the local train station to the main entrance of KSNP and their daily activity budget were studied from February 2011 until July 2011 inclusive of intensive direct observation using the scanning method. Observations revealed that longtailed macaques use most of the their time for moving (20.27%), followed by feeding (18.78%), being inactive (17.05%), grooming (10.84%), playing (10.50%), vocalization (10.36%), mating (7.42%) and the last is fighting (4.78%). Qualitative results found that the interaction between the longtailed macaques group with silvered-leaf monkeys are fighting and grabbing food. The long-tailed macaques also cause disruption in this area such as disturbing the visitors. There is a strange behavior that is rarely seen which is mating behavior between the long-tailed macaque with a cat that was found in the study area. Chi-square test demonstrated that daily activity budget differed significantly among the behaviors. Index Terms-- daily activity budget, long-tailed macaque,