Understanding the variables that promote pro-environmental behaviors (PEBs) can be useful for sustainable development. Research has shown that several factors, including emotions, can influence PEBs. Eco-empathy and helplessness beliefs toward the environment (HBTE) can facilitate or discourage PEBs. To understand the role of these factors, it may be interesting to study their connection with different emotion regulation strategies suggested by Self-Determination Theory. The current study sought to test a model that could explain the associations of dysregulation, suppressive regulation, and integrative regulation with eco-empathy, HBTE, and PEBs. In a sample of 305 emerging adults, we found an association between integrative regulation and eco-empathy, dysregulation, and HBTE. The analyses revealed an indirect pathway from integrative regulation to PEBs through eco-empathy, suggesting the need to implement educational and informational programmes that consider the impact of emotional constraints on PEB implementation in the younger generation.