The present study is predicated on an examination of the strategic background of the integration of agriculture, culture, and tourism. Its central focus is the construction of the IP image of Yangling Agricultural Science City. The brand positioning of the city, informed by the needs of residents and tourists, has been refined to create the “agricultural culture gene pool.” This gene pool has given rise to the “1+3+5” brand system, which comprises one super symbol, three cultural dimensions, and five types of derivation scenarios. The study proposes a closed-loop city image design concept, in which the core elements of wheat, the Weihe River, and Houji culture are extracted through the semiotic deconstruction method. These elements are then combined with the city’s image identity to propose a sustainable design concept. The concept of sustainable design is proposed, and the core elements of wheat, Wei River, and Houji culture are extracted through semiotic deconstruction method. These elements are then combined with the city image recognition system and emotional design theory to complete the IP image design and ecological application system of Yangling. This study contributes to the validation of the “three-chain synergy” effect of agricultural, cultural, and tourism IP on city branding. It also provides a feasible theoretical model and practical path for the transformation, upgrading, and sustainable development of agricultural cities.