Abstract: Background and Objective: Disturbance in Mt. Tumpa forest park, North Sulawesi has affected the diversity of its mammals species. This is caused by habitat degradation due to irresponsible land clearing and illegal loging which leads to forest habitat fragmentation. This threatens the survival of some Sulawesi’s endemic mammals which reside in the forest, such as Macaca nigra and Tarsius spectrum. In this present study, survey was conducted to analyse wild mammals diversity record in forest park, North Sulawesi, Indonesia. Materials and Methods: Species richness, diversity and abundance of recorded mammals across the variety of habitat were estimated. This was done by establishing randomly selected transect lines across four types of habitat: primary and secondary rain forest, shrub, meadow and agricultural land. Species richness was the total number of the species in a community and measured using Margalef’s index (Dmg). Shannon-Wiener (H’) index was used to determine diversity of mammals. Eveness (E) of species distribution was calculated according to Krebs and supported by measurement of Lorenz curve using Excel 2013. Results: The data showed that there were a total of 621 individuals of mammals consist of eleven species and nine families recorded. The most abundant species was tarsier (Tarsius spectrum). The value of Shannon-Wiener index 1.48 indicates that the diversity, the spread of number of individuals in each species and community stability are moderate. While, the value of evenness below one ( 0.62) indicates that there is a dominant species in the community and the species distribution is uneven. In addition, the species richness in this area is moderate based on its value 1.71. Furthermore, the relatively low abundance (0.97) of macaque (Macaca nigra) indicates that the forest habitat has been degraded. Conclusion: The study reveals moderate diversity of wild mammals in Mt. Tumpa forest park. This information shows that hunting and deforestration in this area should be controlled for the sake of better conservation of the endemic and endangered faunal resource. The result of this study will contribute to the wild mammal conservation effort in this area, especially those of endemic species such as M. nigra and T. spectrum.