This paper explores the relation between population growth in Mindanao and the destruction of the forest ecosystem in Mindanao. The history of rapid population growth can be traced back to 1913 when agricultural colonies were set up in Mindanao to open Mindanao to trade and development. The government resettlement program resulted in the degradation of the environment and displaced the indigenous populations. The paper concludes with a discussion of possible maintenance and rehabilitation of the ecosystem.