Abstract:etailed studies on the double fertilization process and its duration of different stages in Panicum miliaceum L. were conducted. The main results are summarized as follows: The whole process of fertilization completes in 3 h after anthesis. The pollen tube reaches the micropyle of ovule in 20 min and enters the embryo sac and releases sperms 30 min after anthesis. The fusion of female and male nuclei occurs in a period of 30 min to 3 h after anthesis. The process of syngamy is almost the same as that of triple fusion, however, triple fusion ends always earlier. Primary endosperm nucleus forms 2 h after anthesis, and then divides. Zygote forms 3 h after anthesis when endosperm contains two free nuclei. The first mitotic division of zygote takes place 8–10 h after anthesis. Zygote has a dormancy period of 5–7 h. The double fertilization is a type of premitotic syngamy.