If empirical evidences show that environmental security is on the United Nations agenda, very few studies try to understand the agenda-setting process of this issue. My thesis research intends to fill this gap by analyzing the process of environmental securitization within the organization. Securitization theories and critical security studies propose a first useful set of theoretical tools. Nonetheless, this communication argues that they are not the only ones, and that Political Ecology could bring an interesting different perspective and encourage an interdisciplinary dialogue. By promoting transdisciplinarity, highlighting social and economical dimensions of environmental conflicts and calling attention to the power and knowledge structures beneath the securitization process, Political Ecology proposes highly relevant additions to the study of environmental securitization within the United Nations. This paper argues that this particular example shows the benefits of collaborations between political ecologists and securitization theorists – and, more generally speaking, International Relations scholars – and therefore advocates for more mutual and constructive dialogue among those different schools of thought.