The pollen tube growth and duration of double fertilization in Adonis amurensis were studied by paraffin section and fluorescence microscopy observation. A. amurensis has a wet column cap. At 1-2 h after pollination, the pollen grain is recognized by the stigma; at 2-4 h after pollination, the pollen grain begins germination; at 4-6 h after pollination, the pollen tube enters into the stigma. A. amurensis is porogamous. About 10 h after pollination, the sperm is released; about 30 h after pollination the egg nucleus and sperm nucleus begin fusing; at 7 d after pollination, a sperm fuses with the egg cell to form a zygote; dormant stage of the zygote is about 8 days long and at 15 d after pollination, the first mitotic division of zygote takes place. The two polar nuclei are not fused before fertilization. At 14-16 h after pollination, the sperm nucleus fuses with a polar nucleus; at 20-22 h after pollination, the sperm nucleus fuses with another polar nucleus and forms a primary endosperm nucleus. The type of double fertilization is premitotic syngamy. This study provides an understanding for the morphological change and corresponding timing of male and female cells in A. amurensis fertilization, confirms the duration of zygote dormancy, and enriches the knowledge of A. amurensis embryological information, which has great significance for A. amurensis breeding and genetic modification.