Abstract: 1. The pollens of Liriodendron Chinese germinated normally, fast and at the nearly same speed on the stigma of the L. tulipifera. 2. The growth rate of the pollen tubes varied widely, most pollen tubes were observed in the embryo sacs of the materiales 120-134 hrs after pollination, while the earliest could be seen 80 hrs after pollination. A few pollen tubes might become swelling in their tips or sometimes bursting or twisting on the mi-cropyle. 3. The growth rate of pollen tubes varied widely with the position of gynecium. The pollen tubes grew fast in the stigma canal and style canal, but slow in the obturator and micropyle. 4. The double fertilization occurred usually 5 days after pollination. The endosperm nuclei and zygote were observed in the materials 10-15 days after pollination. Heart-shaped embryo was observed in the materials 30 days after pollination. And the embryos with cotyledon formed 90 days after pollination. Till 140 days after pollination, the embryo and seed developed to its full size and ran to mature seeds. 5. The average seeding rate of consecutive 3 years was 24. 48% , 15. 04% and 24. 88% respectively, with the highest rate 63. 4% of an aggreagate samara, while the rate was nearly zero before pollination control. 6. A small portion of embryo sacs and micella ware abortive 3-5 days after pollination. A small portion of cotyledon stage-embryo and endosperm was abortive 90 days after pollination.