Abstract: In order to improve corn harvester's grain recovery rate and reduce impurity content of recovered grain，an upper fan shaker-type grain recovery device was designed.Main influencing factors of airflow field were experimentally studied.In addition to removing light debris，the designed airflow field also required that bract leaves could be turned upside down and smoothly discharged out of the machine.In order to explore influence of air distribution plate on airflow field in recycling room，the Fluent module was used for simulation analysis.Simulation results showed that air distribution plate could effectively improve airflow distribution in recycling room.In order to obtain distribution of airflow field in grain recovery room，several measurement points were set in recovery room，wind speed was measured at each point with an anemometer，and posture of bract leaves discharged from peeling device under action of airflow field was observed and analyzed.Fan speed，inclination of wind and operating speed were selected as test factors，and grain recovery rate was an evaluation index.A three-factor and three-level orthogonal field test was performed.The SPSS software was used to analyze variance and mean of test results.Influence of each test factor on test index and order of primary and secondary were obtained.Test results showed that speed of fan had the greatest effect on recovery rate of grain，followed by inclination angle of wind，and effect of operating speed was not significant.The best combination was a fan speed of 1000 r/min and an outflow angle of 15 °.