Abstract: Variation in socioecological characteristic such as activity pattern is an example of how primates adapted to their local environment. In this study, daily activity budget of long-tailed macaque (Macaca fascicularis) was described that confined in Universiti Kebangsaan Malaysia main campus. A comprehensive population survey of the long-tailed macaque was also conducted to determine the population count and group size. Between June 2002 and May 2010, several long-tailed macaque groups were observed via group focal sampling and the behavior continuously recorded. Population surveys indicated that there were nine groups of long-tailed macaques with 600 most individuals located around student residential colleges. Present results indicate that all long-tailed macaque groups spent most of their time in locomotion (18.00-31.36%). Resting (16.13-20.26%) and feeding (16.29-24.02%) accounted as the most activities after moving. However, long tailed-macaques were less engaged in social activities such as playing, vocalization, agonistic, grooming and sexual behaviors. Chi-square test demonstrated that daily activity budget differed significantly among behaviors.