Abstract: Thirteen seed characteristics of 121 longan germplams at the National Field Genebank for Longan in Fuzhou were studied. The coefficient of variation of 13 characteristics ranged from 4.6% to 21.1%. Five characteristics, including seed weight, hilum length, hilum width, hilum width/seed transverse diameter and ratio of seed to fruit weight, showed higher degree of variation and coefficient of variation exceeding 10%. Longan germplams from Vietnam had largest seed weight, while longan germplams from Thailand had lowest ratio of seed to fruit weight and highest edible flesh rate. The fruit weight had significantly positive correlation with the seed weight, longitudinal diameter, transverse diameter, and lateral diameter, as well as hilum length and hilum width. Ratio of seed to fruit weight had very significantly negative correlation with fruit weight and edible flesh rate. The results of principal component analysis showed that 13 characteristics could be reduced into four factors, namely the seed size, hilum size, seed shape and shape of seed tip.