Adopting an integrated method combining FUZZY DEMATEL and ISM，this study constructs an ecosystem model of regional public brand for agricultural products while identifying and analyzing the core elements and their intrinsic relationships within the system，which provides a decision-making basis for the sustainable development of regional public brand for agricultural products under the goal of “double carbon”.It is found that the ecosystem of regional public brand for agricultural products is influenced by multi-dimensional synthesis， encompassing 24 specific factors across 6 main aspects.Among them，the most direct influencing factors involve four key areas including the leadership role of leading agricultural enterprises，low-carbon packaging，cross-border low-carbon practices and the widespread application of public services.In addition，there are 13 intermediate factors，such as consumer responsibility awareness and the influence of the cultural environment，which connect the lower and upper levels of the ecosystem.Finally，seven factors，such as political environment，ecological environment，ecological civilization concept and food security，are identified as essential elements that have a decisive impact on the healthy operation of the entire ecosystem.