Establishing protected areas creates an opportunity to reduce deforestation. This study aims to inform the Congolese government’s efforts to promote forest and biodiversity conservation by assessing the effectiveness of the Yangambi Biosphere Reserve (YBR) in reducing deforestation. Group and individual interviews designed to understand the causes of pressure on forest cover in the Yangambi landscape complemented satellite imagery analyses. The results indicate that deforestation inside the YBR is not significantly different from outside the YBR. They demonstrate the lack of impact of the YBR in reducing deforestation. The dependence of communities on forest resources would have led to an explosion of bare and fallow land replacing forest areas. A sufficient budget allocation for conservation coupled with capacity building of managers to implement integrated conservation projects could offer alternative livelihoods at the community level, reduce pressure on natural resources from local development and ensure biodiversity conservation in and around the YBR.