At present, Guangxi agricultural industry is facing the dilemma of large but not strong, and it is urgent to explore effective strategies for industrial upgrading and transformation in order to promote the high-quality development of agricultural economy. In order to explore the path of high-quality agricultural development in Guangxi, Wuming mandarin orange was taken as a case study to explore the mechanism and depth of its three-chain fusion. It is found that the three-chain integration effectively promoted the upgrading and transformation of the citrus industry. Under the guidance of the government, Wuming mandarin orange industry builds smart agriculture through the integration of production, learning and research, and cultivates a group of leading enterprises to drive farmers to produce and plant, which initially shows the “smart orchard” planting and production management mode of intelligent data. At the same time, the introduction of intelligent processing equipment and modern marketing management, in order to enhance the competitiveness of the downstream industry. In the process of the construction of smart agriculture, the three chains gradually integrated with each other, and the degree of integration is continuously deepened. Finally, by constructing the fuzzy evaluation index system of three-chain fusion, the current three-chain fusion of the mandarin orange industry is evaluated, and it is concluded that the three-chain fusion of the citrus industry is in the cultivation stage, and the depth of the integratation of the three chains needs to be further enhanced.