As an important component of the artificial intelligence, machine learning has not only attracted wide attention in the academic world, but also has great application potential in the agricultural industry. Machine learning is an advanced technology for smart agriculture that can develop advanced methods of disease detection and classification. In view of the application potential of machine learning in the field of agriculture, the concept and classification of machine learning are described through the research of machine learning related literature. This paper summarizes the application status of machine learning in smart agriculture by combining machine learning with the management of crop growth period, planting conditions and yield requirements.Major applications of machine learning, including crop, water, soil, and animal management, are investigated, revealing its important role in revolutionizing traditional agricultural practices. This paper focuses on the application of machine learning in pest identification and control, crop yield, water resource analysis and soil analysis. Combined with the problems existing in the application of machine learning in smart agriculture, the future research direction is proposed.