The predatory ant, Myopopone castanea Smith, F. (Hymenoptera: Formicidae) has been reported as a natural enemy for the oil palm pest, Oryctes rhinoceros Linnaeus (Coleoptera: Scarabaeidae). This study aims to determine the distribution of the predatory ants among selected oil palm Elaeis guineensis Jacq. (Arecales: Arecaceae) plantations of North Sumatra Province. The presence of M. castanea colonies was conducted by checking several fallen and rotting oil palm trunks. Conservation efforts to ensure a sustainable ant population were made by inserting M. castanea colonies into each of the two deteriorating palm trunks, which were identified as sustainable habitats for the ants. The palm trunks were placed at the frond stacks and trunk heaps and kept in the open field for five days. It was discovered that M. castanea colonies, with variable ant counts in each colony, are present on several oil palm plantations. The results indicated that the frond stacks contained more dead prey and ants than the trunk heaps. Since ants do not have a preferred habitat for nest-building, rearing the ant colonies in the frond stacks should provide a higher population of ants compared to the trunk heaps.