Abstract:The key to agricultural modernization lies in the modernization of agricultural science and technology. Advancing this modernization at the county level can provide strong support for accelerating the development and revitalization of agriculture and rural areas. Using Guangdong counties as an example, through theoretical analysis and learning from domestic and foreign experience, it is constructed the supply and demand model of agricultural science and technology,to reveal the evolution mechanism of the typical model of agricultural science and technology modernization at county level, it includes industry-university-research-practice cooperation model, enterprise-driven model, socialized service model, and industrial chain aggregation model. These models aim to address serious problems in county agricultural science and technology, such as the lack of scientific and technological innovation talents and high-level platforms, weak science and technology promotion, and low levels of enterprise innovation.To promote county agricultural science and technology modernization, it is suggested to innovate the mode of scientific and technological cooperation in all aspects of the county, enhance the chain of scientific and technological innovation, strengthen the modernization of human resources, and deepen reforms and system innovation. These suggestions provide a useful reference for exploring the mechanisms, models, and practical paths of science and technology in supporting county rural revitalization..