Abstract: The spatial difference of regional urbanization development has great impacts on agricultural productivity. Based on a 14-year spatial panel data of 129 cities in the Yangtze River economic belt from 2005 to 2018, this paper analyzed the agricultural productivity by the Stochastic Frontier Analysis (SFA) method and evaluated the spatial spillover effects of urban social and economic development on agricultural productivity by the spatial panel Durbin model from both global and local perspectives. Results show that: 1) from 2005 to 2018, the agricultural productivity of the cities in the Yangtze River economic belt is increasing year by year, but the overall level is low with huge spatial heterogeneity. The high value area is mainly around Shanghai, Wuhan, and Chongqing; 2) the development gap between urban and rural areas is the main factor hindering the improvement of agricultural productivity in regions, especially in the upper reaches, while non-agricultural economy and traffic conditions play important and positive roles in promoting global agricultural productivity; 3) agricultural productivity in upstream cities are mainly affected by the direct effect of urban development, while the agricultural development of middle and downstream cities is greatly affected by the indirect effect of urban development. Therefore, this study believes that actively developing non-agricultural industries, improving transportation and other infrastructure conditions, promoting the flow of agricultural inputs, narrowing the development gap between urban and rural areas, promoting regional balanced development are the main policy recommendations to improve agricultural productivity in the Yangtze River Economic Belt.