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In order to solve the difficulty of high speed and precision control of wheat in corn straw covered ground of Huaibei Plain and simplify the existing wheat seed supplying pneumatic type mechanism, a inclined parabolic cell wheel seed feeding device for wheat was designed. The structure and working principle of wheat precision seed device was described, the relevant parameters were analyzed and determined, the curve limit equation of cell and the mechanical model of wheat seed supplying process was established, and then taking the cone angle, speed of cell and wheel number as test factors, seed feeding rate, stability coefficient of variation of seed feeding and damage rate were taken as test indexes and a performance experiment was carried out. Experimental results showed that parabolic cell with a dip angle of 40° had better stability, whose stability coefficient of variation of seed supplying was less than 1.8% and damage rate was below 0.2%;under the condition that the amount of cell wheel was 1~5 and working speed was 10~100r/min, wheat seed feeding rate, which was ranged from 35g/min to 1500g/min, was rising as the number and speed of cell wheel was increased;stability coefficient of variation of seed feeding, which was less than 2.0%, was decreased as cell wheel number was increased, and it was decreased first and then raised as cell wheel speed was increased;according to the variable feeding matching experiment with the mathematical model of sowing amount per hectare, which was established by seed feeding device for wheat with the installment of 5 cell wheel, a large range of variable supplying, whose stability coefficient of variation of seed supplying was less than 2%, was achieved when simulation advancing velocity of the equipment was less than 9.8km/h. The field experiment showed that the planting density of direct seeding wheat was 230~270 strain per square, and homogeneity coefficient of variation of seed supplying was 21.97%. Inclined parabola cell wheel proposed can realize a wide range of wheat seed supplying and simplify the structure of seed supplying device, in order to design a high performance wheat variable seed sowing machine for corn straw mulch in Huaibei Plain and provide the basis.