Using Origin software, the grain filling process of hybrid wheats 1–12 and 8-1-54 and their parents was fitted by Richards equation W = A/(1 + Be−kt)1/N on computer in order to study the characteristics of grain filling in hybrids wheat. The active grain growth period of hybrid wheats 1–12 and 8-1-54 were longer than that of their parents respectively, and their final grain weight was higher than that of their parents respectively. These results suggest that hybrids 1–12 and 8-1-54 have the higher capacity of graining filling than their parents and that may be associated with longer RGFP and higher maximum grain-filling rate. It was also found that Richards equation was more suitable for fitting the grain filling process of wheat than Logistic equation.