Abstract: Product digital modeling is a technology that converts physical products into digital models, which can quickly and accurately create product digital models and realize product virtual design, simulation analysis and optimization. Taking the design of combine harvester as an example, the paper discusses the method of combine harvester design and analysis based on product digital modeling technology, analyzes the modeling effect, and also proposes the future development trend and research direction of product digital modeling technology in agricultural machinery production and manufacturing. The research results provide useful experience and guidance for the digital design and performance optimization of agricultural machinery, and provide technical reference and reference for promoting the process of agricultural modernization.