The growing global interest in biodiversity conservation and the role of forestland sustainability in climate change mitigation has led to the emergence of a new specific field of global environmental governance that we called ‘forest diplomacy’. With the largest tropical forest area after the Amazon, Congo Basin countries (CBc) constitute a major negotiation bloc within global forest-related governance arenas. Despite this position, CBc seems embedded in a failure trap with respect to their participation in forest diplomacy arenas. This paper examines the major causes of the recurrent failures of CBc within forest diplomacy. A qualitative empirical approach (including key informant interviews, groups discussion, participant observation, and policy document review) was used. From a conceptual and theoretical perspective, this research combines global and political sociology approaches including environmental and blame avoidance works. The main finding reveals that the recurrent failures of CBc in forest diplomacy are partly due to the lack of strategic and bureaucratic autonomy of CBc that strongly depend on financial, technical, and knowledge resources from Western cooperation agencies or consultancy firms. Our discussion highlights that this dependency is maintained by most of the key actor groups involved in forest diplomacy related to CBc, as they exploit these failures to serve their private interests while avoiding the blame of not reducing deforestation and biodiversity loss in the Congo Basin.