In order to solve the problem of the first season rice pile rolled by the track of the harvester in the production process of ratooning rice, a spatially planetary gear train planting mechanism with large deviation, direct harvesting and small lateral hole transplanting trajectory was proposed, starting from the perspective of mechanical planting with the condition of the effective number of strains per unit planting area and the crawler walking row distance by reasonably increasing the planting row spacing. Firstly, planning the wide and narrow rows trajectory and determining the key position posture by combining with planting agronomy, geometric equations for key 3 poses containing spatial constraints were established by constructing a simplified spatially open-chain 2R mechanism model. The parameters were solved by using homotopy algorithm. Then, the relative angular displacement relationship between the input and output axis of the open chain mechanism was obtained based on fitting and optimizing parameters. The mechanism drive ratio and the non-circular gears pitch curve were determined. The spatial trajectory that meets the transplanting requirements was recovered. Finally, a kind of wide and narrow rows transplanting mechanism of ratooning rice was designed by coupling the motion of the two rotating axes of the open chain mechanism with the non-circular gear pair, which was driven by the plane non-circular gear and helical gear. Virtual simulation and prototype test were carried out, and the results showed that the actual motion trajectory and attitude of the prototype were basically consistent with the theoretical design. The spatial track satisfying the characteristics of wide and narrow rows transplanting of regenerative rice with large offset from taking seeding to pushing seeding ΔS1 was 65.59mm, side push seedling angle γ1 was 16.13°and side hole width ΔS3 was 23.69mm, which verified the feasibility of gear train wide and narrow rows transplanting mechanism design.