Encouraging the development of rural innovation and entrepreneurship，fully stimulating the vitality of rural innovation and entrepreneurship，will provide ample intrinsic momentum and significant development opportunities for promoting county-level economic growth.Utilizing the latest “Rural Innovation and Entrepreneurship Index” published by the Zhejiang University Cater-Enterprise Research Team，based on balanced panel data from 1836 counties in China between 2014 and 2021，an empirical examination was conducted to investigate the impact effect and mechanism of rural innovation and entrepreneurship on county-level economic growth.The results indicate that：（1） Rural innovation and entrepreneurship can significantly promote county-level economic growth.For every 1% increase in the level of rural innovation and entrepreneurship，there is a 4% increase in county GDP；（2） In regions with labor outflows，better physical financial services，and digital inclusive financial services，as well as since the implementation of the Rural Revitalization Strategy，the driving role is more pronounced；（3） Mechanism tests show that rural innovation and entrepreneurship mainly promote county-level economic growth through fostering high-quality and full employment，stimulating consumption vitality，and advancing industrial structure upgrades；（4） the impact of rural innovation and entrepreneurship on county-level economic growth exhibits threshold effects，meaning that its driving role can only be fully realized when the intensity of government intervention is maintained within a reasonable range；（5） Further analysis reveals that rural innovation and entrepreneurship can also promote county-level economic high-quality development by facilitating balanced industrial development and regional green and low-carbon transitions.Therefore，it is necessary to further support the integrated development of rural innovation and entrepreneurship，focusing on promoting high-quality and full employment，stimulating consumption vitality，and advancing industrial structure upgrades as key points，while enhancing the efficiency of government services and promoting the construction of an effective government as guarantees，to gather sufficient impetus for county-level economic growth and high-quality development.