This study focuses on addressing quality supervision issues related to opportunistic behavior within the geographical indication product supply chain. It constructs an evolutionary game model comprising suppliers, distributors, government, and network media. Through analysis, it examines the influence of key factors on the decision‐making dynamics of game participants and presents management suggestions accordingly. The findings are as follows: firstly, the dual supervision model with the assistance of network media can compensate for the regulatory gaps of the government's single supervision model. Secondly, the credibility of network media plays a pivotal role in determining the efficacy of public opinion supervision. With high credibility, measures such as increasing the synergy coefficient, imposing higher fines or compensation amounts, and enhancing the impact of reputational factors can all restrain the misconduct of operating entities. Conversely, when credibility is low, not only does the supervisory function of network media falter, but it also leads to reputational damage for both the operating entities and the government. Thirdly, differentiated management should be adopted for entities in different nodes of the supply chain; higher constraint intensity should be imposed on distributors compared to suppliers. The outcomes of this study provide some analytical paths for supply chain quality supervision and corporate behavior management and underscore the significance of collaborative regulation for sustainable industry practices.