The main grain producing areas are generally faced with the “Impossible Triangle” problem of ensuring national food security, improving farmers’ planting income, and expanding the local fiscal and taxation economy. How to build regional public brands with homogeneous grain and food, and how to coordinate food security and industrial value-added are realistic issues to be responded to in the field of rural industrial revitalization. Taking Shanxi Yuncheng flour, a national geographical indication product, as the research object, based on the “special” and “excellent” strategy of Shanxi agriculture, this paper integrates Porter’s five forces model and SWOT analysis framework to analyze the opportunities, weaknesses and market competition pattern of Yuncheng wheat public brand development from the perspectives of agricultural cultural endowment, raw material supply, quality advantage and industrial foundation. The study found that the core path to solve the “Impossible Triangle” of grain industry development is the collaborative linkage of primary, secondary and tertiary industries. The primary industry relies on the high-quality wheat base to promote green standardized production to consolidate the quality foundation of raw materials; the secondary industry eliminates backward production capacity, extends the wheat intensive processing chain to improve the added value of products; the tertiary industry deeply excavates the Yellow River farming culture and local pasta resources, and builds differentiated regional public brands through cultural empowerment and the industrialized operation of characteristic snacks. The study establishes a four-dimensional brand development strategy of “cultural addition, quality improvement subtraction, value-added multiplication and capacity division”, forms a multi-layer brand matrix of “regional public brand+enterprise brand+product brand”, and promotes the integration and reconstruction of industrial chain, value chain and supply chain. This study provides a reproducible theoretical idea and practical reference for Fenwei plain, Huang Huai Hai and other similar major grain producing areas to balance food security and industrial economic benefits, and cultivate regional public brands of grain.