With the hybrid rice ‘Jieyou 8’ as the tested material, and using two elements two orthogonal rotational regression combination design, the relationship between the yield and nitrogen application rate and planting density was studied. A mathematical model of two factors with yield was established: Y=10 820.56+114.16X₁+808.93X₂-1204.14X₁²-928.38X₂²-182.29X₁X₂. Through optimization, the optimum amount of nitrogen applying rate o‘fJieyou 8’was 270 kg/hm², the best planting density was 145 strain/hm². At this density and nitrogen conditions, high yield of 11 290.56 kg/hm² can be reached.