With the progress of the times, traditional research methods cannot well meet the urgent needs of sustainable development of agricultural economy. Therefore, this article aims to study the application of AI technology to promote sustainable development of agricultural economy. Firstly, this article utilizes support vector machines in machine learning techniques to establish a prediction model and optimize the planting optimization techniques in the R area; secondly, it uses deep reinforcement learning technology to construct an intelligent scheduling system for R area, optimizing the scheduling of intelligent agricultural machinery operations; next, this article constructs a long-term and short-term memory network model to make intelligent market predictions based on market data in the R region. Finally, this article takes the irrigation system in R area as an example to conduct experimental evaluation of sustainable development indicators for agricultural economy. The results showed that the irrigation efficiency and water resource utilization rate of irrigation systems using AI (Artificial Intelligence) technology were 24.05% and 25.64% higher than traditional irrigation systems, respectively. It can be seen that the application of AI technology can effectively promote the sustainable development of agricultural economy.