Abstract: In order to reduce the rate of snapping loss and broken stalk about plate-type header of corn harvester，optimums working parameters which included three factors of speed of stalk snapping roller，height of corn header and working speed of corn harvester were found.Design and analysis of response surface for three factors were made using SAS software.Stress and deformation characteristics of stalk and stalk cross section were analyzed by ANSYS software.Results showed that obtained decided of coefficient were 0.84 and 0.90 about loss rate and the rate of broken straw regression mode，when search radius was 1，loss rate of ridge maximum and minimum response value were 5.19% and 2.36%，rate of broken stalk，ridge analysis the maximum and minimum were 14.3% and 10.32%.Compression in the short axis direction was very easy pinch corn stalk compared with long axis.Experimental results provided theoretical basis for the development of corn mechanization harvesting technology.