The stubble clearance efficiency of instrument is an important indicator of notillage seeding under the mode of protective farming mode. Based on the conservation tillage model in Northeast China, a straw cleaning mechanism with concave structure was designed and improved on the 2BMZF-2 notill planter produced by Jilin Kangda Agricultural Machinery Co., Ltd. In addition, factors such as the operating speed of planter in the stubble clearance mechanism, the soil contacting depth of stubble clearance wheel and the movement declination angle of stubble clearance wheel were analyzed. The key parameters of stubble clearance mechanism were identified according to the simulation analysis and the analysis on the results of field trial, which can be listed as follows: the diameter of stubble clearance wheel disc was 350mm, the angle between the movement direction of the stubble clearance wheel and the working direction of notillage planter was 37.5°, and the soil contacting depth was 70mm. The result of the experiment indicated that the stubble clearance rate could reach up to as high as 8361% at the operating speed of 2.77m/s. The stubble clearance mechanism designed could effectively clean the seedbed and prevent the blocking of instrument, which, in the meantime, was suitable for the uniform ridge farming mode of maize as well as the wide and narrow row farming mode of maize.