Abstract: Aimed to the problem of corn leakage picking, which was caused by raking and conveying device in the process of corn harvest, the influence of both the way of harvest in row and the height of raking finger on the plant down rate was studied in the paper. The results showed that the harvesting way combining the harvest in middle row with high raking location of raking finger could effectively decrease the plant down rate and reduce the spike leakage loss for 3-row of self-propelled corn harvester. The deviation between plant row and the snapping rolls of outside of corn harvester could be decreased from 26 to 13 cm when the harvester with group distance between snapping rolls of 68 cm was experimented on the row distance of corn plant of 55 cm, and the plant down rate could be further decreased to 1% when the raking finger height was up to 40-45cm .