The interaction between long-tailed monkey, Macaca fascicularis Raffles (Primate: Cercopithecidae) and human, Homo sapiens Linnaeus has been increased in last few decades due to the tremendous increase in the populations of both species in Botanical Gardens Penang (BGP), Malaysia. They were interrelated in their environment; therefore, M. fascicularis has been disturbed due to human activities. In turn, M. fascicularis re-emerged with an effective and high-level reaction to human population. The present research was conducted to observe the interaction between M. fascicularis and H. sapiens by using scan sampling method in BGP, Malaysia during March 2012-February 2013. Their behavioural interactions were found significant (p<0.001) with all aspects. However, the highest behaviour of M. fascicularis was attacking (2.2±0.9) and the lowest was vocalization (0.2±0.4) compared with its all activities (X2=1832.9; p<0.001; n=215), moreover, the highest behaviour of H. sapiens was giving food (2.16±0.8) and the lowest was hand clapping (0.2±0.4) compared with all activities (X2=927.6; p<0.001; n=119). The attacking behaviour of M. fascicularis was positively correlated with feeding, eating, grooming and snatching, however, it was negatively correlated with running, vocalization, playing and exploiting garbage. From the human activities, the feeding was positively correlated with throwing food, confliction and going close, however, it was negatively correlated with gesture, running, hand clapping and playing. It was concluded that the behaviour of M. fascicularis was insecure in BGP where both were coexisted. The management of respective locales were recommended to formulate practical strategies to avoid or decrease the interaction between both.
