Corn has become the top substitute for rice and wheat, thereby significantly influencing the lives of people involved in increasing corn production. The technology of corn harvesting has been developing toward the direction of mechanical harvesting. At present, corn grain harvesting can complete harvesting, threshing and cleaning process at one time, which reduces operation process and improves working efficiency. It is the development trend of corn harvest. However, the corn grain moisture content restricts the development of corn grain harvest. In order to solve the problem of high maize kernel damaged rate and high unthreshed rate during the corn harvest in Huang-Huai-Hai region, a transverse axial flow corn threshing test system was designed which used flexible tooth and elastic short rasp bar as threshing elements. In order to make the material in the cylinder have a transmission capacity, the flexible tooth and elastic short rasp bar were arranged in four heads. The test system adopted grid concave. Six spiral guide bars were arranged at the inner wall of the cover to assist the speed of material movement. The key design parameters of this type threshing system were calculated and explained. For the sake of reliability, the dynamic balance simulation was carried out with ADAMS software and YYW-1000 dynamic balance machine checked the accuracy. The threshing cylinder speed, concave clearance and feed rate were selected as the influence factors, and the maize kernel damaged rate and unthreshed rate were selected as the performance indexes in the orthogonal experiments. The optimal experimental results were as follows: threshing cylinder speed was 450r/min, the concave clearance was 40mm and the feed rate was 8kg/s. And the corresponding performance indexes were as follows: the maize kernel damaged rate was 0.65%, the unthreshed rate was 0.59%, which could completely reach the requirement of the national standards in China. The research result of the threshing system provided reference for design of the type of corn harvester.