[Objective] The the temporal and spatial evolution law of non-point source pollution on cultivated land in the Dongting Lake plain from 2009 to 2019 was studied to define the decoupling relationship between cultivated land non-point source pollution and agricultural production in order to provide a scientific reference for the treatment of non-point source pollution on cultivated land in the Dongting Lake plain.[Methods] The application rates of chemical fertilizers and pesticides in addition to grain yield per unit area were used to describe the status of cultivated land non-point source pollution and agricultural production in the Dongting Lake plain. Spatial analysis and a decoupling model were used to determine the temporal and spatial evolution law and the decoupling relationship between non-point source pollution on cultivated land and agricultural production in the Dongting Lake plain from 2009 to 2019.[Results] ① From 2009 to 2019, the application rates of chemical fertilizers and pesticides in the Dongting Lake plain initially increased and then decreased, and exhibited obvious spatial differences. The productivity of chemical fertilizers and pesticides showed an overall upward trend; ② From 2009 to 2019, grain yield per unit area in the Dongting Lake plain showed an inverted U-shaped trend, with obvious spatial differences; ③ The decoupling relationship between grain yield per unit area and the rates of chemical fertilizer and pesticide applications in the Dongting Lake plain showed obvious stage characteristics:the first stage was a fluctuation period (2009-2013); the second stage was a strong decoupling period (2014-2015); and the third stage was a weak negative decoupling and declining decoupling period (2016-2019); ④ The decoupling relationship between agricultural production and cultivated land non-point source pollution in the Dongting Lake plain gradually showed high convergence and aggregation characteristics on the county-level spatial scale.[Conclusion] Efforts should be taken to further strengthen the prevention and control of the source of non-point source pollution on cultivated land through the use of a variety of measures in order to improve grain yield, and to finally realize the strong decoupling between cultivated land non-point source pollution and agricultural production.