The coordination and sustainable development of supply and demand of agricultural science and technology talents are the inner power to promote rural revitalization and realize agricultural modernization. Based on the provincial panel data from 1999 to 2018， the coupling coordination degree model was used to analyze the changing characteristics and spatial-temporal dynamics of the coupling coordination level of supply and demand of agricultural science and technology talents in 31 provinces and cities in mainland China. The results show that： From the perspective of time， the mean value of coupling coordination degree of supply and demand of agricultural science and technology talents in China has been going down in the past 20 years and the overall coupling coordination stands at the lower level. Furthermore， the coupling coordination degree of 31 provinces and cities has spanned 10 coupling coordination levels， and most provinces and cities are in the stage of “being on the verge of maladjustment and recession”and “barely coordinated development”， with few provinces and cities having achieved coordinated development. In spatial terms， the coupling coordination level is relatively high in agricultural developed provinces and the central region hold the highest coupling coordination level among four regions followed by western， northeast and eastern regions. Furthermore， the differences between regions are significant. Hence， suggestions are put forword to promote the coordinated development of the supply and demand of agricultural science and technology talents， such as improving the ability of talent supply， adjusting the structure of talent supply， optimizing the arrangement of policies and institutions to promote the rational flow of talents.