Abstract: In order to solve problem that existing grain combine harvesting equipment is difficult to adapt to harvest characteristics of buckwheat，a stripping apparatus with air suction for buckwheat was developed.Feeding velocity，inlet air-flow pressure and cylinder speed were selected as impact factors，harvest rate and splash loss rate were taken as evaluation indexes for experimental study.Orthogonal design method was used for test design with influence factors of feeding velocity，inlet air-flow pressure and cylinder speed.By orthogonal test，it could be known that factors affecting harvest rate in order of their importance were cylinder speed，inlet air-flow pressure and feeding velocity，the largest effect on splash loss rate was caused by inlet air-flow pressure，and followed by feeding velocity and cylinder speed.Taking maximum harvest rate and minimum splash loss rate as optimization objectives，best combination of parameters was cylinder speed of 500 r/min，inlet air-flow pressure of 80 Pa，feeding velocity of 0.5 m/s.Harvest rate was 86.37 % while splash loss rate was 9.23% under this optimal parameter combination.The result could provide reference for related design of buckwheat mechanized harvesting equipment.