The Grain for Green Project (GGP) was implemented over 20 years ago as one of six major forestry projects in China, and its scope of implementation is still expanding. However, it is still unclear how many ecosystem services (ESs) the project will produce in the future. The GGP’s large-scale ecological monitoring officially started in 2015 and there is a lack of early monitoring data, making it challenging to predict the future ecological benefits. Therefore, this paper proposes a method to predict future ESs by using ecological monitoring data. First, a new ensemble learning system, auto-XGBoost-ET-DT, is developed based on ensemble learning theory. Using the GGP’s known ESs in 2015, 2017, and 2019, the missing ESs of the past decade have been evaluated via reverse regression. Data from 2020 to 2022 within a convolution neural network and the coupling coordination degree model have been used to analyze the coupling between the prediction results and economic development. The results show that the growth distributions of ESs in three years were as follows: soil consolidation, 3.70–6.34%; forest nutrient retention, 2.72–.71%; water conservation, 2.52–6.09%; carbon fixation and oxygen release, 3.00–4.64%; and dust retention, 3.82–5.75%. The coupling coordination degree of the ESs and economic development has been improved in 97% of counties in 2020 compared with 2019. The results verify a feasible ES prediction method and provide a basis for the progressive implementation of the GGP.