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Conservation tillage technologies mainly contain no/minimum tillage seeding, crop residue management, subsoilling technology and topsoil tillage technology. Based on the analysis of global adoption, technical modes and application benefits of conservation tillage, this paper reviewed the working principle, technical characteristics and developing trends of conservation tillage in four key parts, including crop straw and residue management, topsoil tillage technologies and machines, no/minimum tillage seeding key technologies, and subsoiling technologies. Combined with the research progress and application requirements of conservation tillage in China, current technical difficulties were analyzed and generalized, and future research emphasis and development direction were provided as following aspects: improving processing craft and materials of machine’s key components, strengthening basic theoretical research, optimizing machine structure, enhancing the intelligent measuring and controlling technologies and information management ability of machines, combination of agricultural machine with agronomy under conservation tillage, forming regional-suited technical pattern and system.