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As the core equipment of agricultural machinery, the tractors are rapidly becoming of increasing importance to agriculture. The technical advance of tractor products reflects the degree of national agricultural mechanization and the level of agricultural modernization. In recent years, novel structures and devices have been emerging on tractors, of which the technical level is constantly improved, and the overall performance keeps enhancing with the extensive application of various new technologies. Based on the analysis of the tractor development world-widely, the urgency and necessity of tractors to achieve automation, intelligentization and informatization were proposed. The latest researches on agricultural tractors in engine emission controlling, new energy altering, power shifting, continuously variable driving, front axle suspending, cab comforting, hitch electrohydraulic controlling, bus networking and system informatization were summarized. Meanwhile, the basic principles and characteristics of related technologies of each system were expounded combining with the application of specific products. Considering the national situation, the development direction of tractor technology was prospected with a historical and in-depth review of its development process. The precision agricultural system, which integrated high efficiency, energy saving, environmental protection and intelligence, benefiting from the rapid developing technologies of cloud computing, big data and internet of things, was thought to be a new model of future agriculture. Accordingly, intelligent perception and decision, efficient driving and remote controlling of intelligent tractors, which played an important role in the precision agriculture, were speculated to be the new bright spot and direction of tractor technology development in the future.