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This paper describes the significance of transplanting agronomy for the development of China agriculture, and points out that the transplanting machine, especially the potted-seedling transplanting machine, will be the one to substantially increase the per unit area yield of grain and play the positive role of transplanting for increasing grain production in North China Cold Area and promoting farmers to get rich. After reviewing the history of transplanting equipments in the world, it is indicated that the development of transplanting machinery is generally divided from low to high into three stages, the slide-mechanism stage, bar-mechanism stage, and rotary-mechanism stage. This paper analyzes the development status and research level of the transplanting machinery at home and abroad, and forecasts the prospects of development trend. It is emphasized that in order to enter the rotary-mechanism stage of the potted-seedling transplanting machinery, the researchers must master the mechanism and related theories, computer knowledge and the operation, and secondary development skills of commercial software. The paper also puts forward a series of proposals on some current domestic important development trend.