Sulawesi is an important island for primates. All 17 species that are found there are endemics. The island also includes contact zones between species of macaques (genus Macaca) where hybrids may arise. Sulawesi continues to be deforested, especially in the lowlands most suitable for estate crops and other agricultural products.

Remaining habitat for P. tapanuliensis is threatened by forest fragmentation, habitat degradation, and conversion that are slated to continue. These are critical factors for the survival of large primates, and particularly Sumatran orangutans, including P. tapanuliensis. Presently, individuals of this species are divided among three forest fragments in the Batang Toru region of Sumatra.