Wind tunnel devices play an important role in studying the lodging resistance of rapeseed in strong wind environments. The wind tunnel model of rapeseed lodging resistance test was established based on computational fluid dynamics software Fluent. The design of parameter and simulation tests on key parts of the wind tunnel including diffusion section, stabilization section and contraction section were conducted. The effects of key parts of the wind tunnel on the quality of the wind tunnel flow field were analyzed. The optimal design scheme was selected with orthogonal experiments. The results showed that the variation coefficient of wind velocity at the outlet of the wind tunnel increased when the length of the shrinkage section Ls increased, and the quality of airflow decreased in the single factor experiment. As the length of the stable section Lw increased, the coefficient of variation of wind tunnel outlet wind speed first decreased and then increased. When Lw was 1 000 mm, the coefficient of wind speed variation was the lowest and the airflow quality was the best. The wind speed variation coefficient of wind tunnel outlet first decreased and then increased with the increase of the outlet length of the stabilization section of the damping net distance. When the damping net was 0.65Lw away from the wind tunnel outlet, the variation coefficient of wind speed was the smallest. Among the 9 orthogonal experimental schemes, when the shrinkage section length was 600 mm, the stabilization section was 800 mm, and the damping net was 0.65Lw away from the wind tunnel outlet, the average variation coefficient of wind speed in the corresponding wind tunnel test area was 0.139. The wind speed was more stable than other schemes, and the airflow quality was the best. It is indicated that there is no significant difference between the measured wind speed and the simulation value in scheme 2 wind tunnel. It will provide data support and proof for the design of wind tunnel.