Abstract: Revealing the factors that influence the willingness of the public to participate in grassroots river chiefs is crucial for improving both the grassroots river chiefs system and public engagement in environmental protection. Based on 600 public questionnaire responses from the Sichuan-Chongqing region in the upper Changjiang River, we employed the theory of planned behavior (TPB) and norm activation model (NAM) to investigate these factors from both rational and moral perspectives. The research reveals that subjective norms, perceived behavioral control, and personal norms have a significant positive impact on the willingness of the public to participate. Among these, personal norms exhibit the largest path coefficient, making them the key factor affecting participation willingness. Responsibility attribution plays a partial mediating role between consequence awareness and personal norms, while personal norms partially mediate the relationship between consequence awareness, responsibility attribution, and participation willingness. When consequence awareness and responsibility attribution activate personal norms, it effectively enhances the public′s willingness to participate.