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Mechanized seeding is an important part of agricultural mechanization. The planter mainly transports seeds from the seedbox to the seedbed obeyed a reasonable agronomy position, which would create a suitable environment and uniform space for seed germination and plant growth of individual and group. For this purpose, the precision planter applied precision seeding technology and reposeful seed migration technology to guarantee the seed placed in the reasonable seedbed position by singulating the seed orderly from seedbox and maintaining the singulated state to delivery to the seedbed. The seed migration process was a process of organizing multiple links in series. The seed guiding step was a connecting link between the preceding step of seed discharging from the seed metering device and the following step of settling in the seedbed, which affected the orderly state of seeds in the presequence process and determined the uniform distribution of subsequent seeds in the seedbed. The research of seed guiding technology and the device of the planter was reviewed. According to the concept of object degree of freedom constraint, the seed guiding was generalized into three types: seed unconstrained, seed underconstrained, and seed fullyconstrained. The seed movement constraints, technical characteristics, and applicable objects of the three technical principles and devices were analyzed systematically. Combining the research progress of domestic and foreign technical equipment and the technical requirements of mechanized seeding, the development of seed guiding technology and device was discussed. The research provided a reference for the research of seed guiding technology and the innovative design of seed guiding devices.