Abstract: 【Objective】 In order to explore the effects of planting density on the grain filling characteristics and yield of evenly planted winter wheat. 【Method】 Two different panicle type varieties of multi-panicle type Xindong 22 (A₁) and large-panicle type Xindong 50 (A₂) were taken as materials, with the planting densities of 123×10⁴, 156×10⁴, 204×10⁴, 278×10⁴, 400×10⁴ plant/hm², Logistic equation was fitted to simulate the grain filling process, and the wheat grain filling parameters were analyzed. 【Result】 The results showed that the fitting decision coefficients of different panicles were all above 0.996 which could accurately reflect the filling process. With the increase of planting density and the reducing of plant spacing, the grain yield and the grain filling rate of different panicle varieties at the filling stage showed a decreasing trend. The 1,000 grains weight of wheat was positively correlated with the maximum and average filling rate. The grain yield was positively correlated with the grain filling, whereas, it was not significantly correlated with the duration of grain filling. 【Conclusion】 Under the condition of uniform sowing, the suitable planting density of multi-panicle type Xindong 22 is 156×10⁴ plants per ha, and that of large-panicle type Xindong 50 is 278×10⁴ plants per ha.