Abstract:No. 244 and No. 5 open-pollinated seeds in primary seed orchard for Chinese fir (Cunning hamia lanceolata) grafting were used as the test material for studying the relationship between ultrastructural changes and seed vigour during germination. The result showed that No. 244 was high-vigour seed and No. 5 was low one. During germination of Chinese fir seeds, increase of number and rate of development of mitochondria (Mt), golgi body (GB) and rough endoplasmic reticulum (RER)etc. of the high-vigour seeds No. 244 were earlier and faster than that of the lower-vigour seeds No. 5, Resolution power, quantity of starch grain (ST) and quantity of liposome (L) were also more than low one. All these showed that there exist close relationship between changes of cell ultrastructural and seed vigour during germination of Chinese fir seeds.