Abstract: It is the core strategy of multi-generation genetic improvement to maintain a reasonable genetic diversity and clear genetic background in breeding populations during the Chinese fir genetic improvement. The genetic materials, which were conserved in the Chinese national germplasm bank, were analyzed systematically by 52 pairs of SSR markers developed. The genetic diversity in the 1^st breeding populations was evaluated based upon the molecular level of SSR markers. The results showed that there were 254 polymorphic SSR loci detected by 52 pairs of SSR primers, of which each SSR marker produced polymorphic loci alleles ranged from 2 to 8, and all sites observed number of alleles, numbers of effect alleles, observed heterozygosity, Nei’s gene diversity and Shannon information index were 4.88, 2.32, 0.43, 0.50 and 0.98, respectively. The five evaluation indices for the level of genetic diversity were consistent. Observed number of alleles, effectives numbers of alleles, observed heterozygosity, Nei’s gene diversity and Shannon information index were different among 52 pairs of SSR markers, and their coefficient of variation were 24.88%,44.75%,34.20%,34.89% and 33.59%, respectively. The average value of genetic identities was 0.693 3 among 93 samples, ranged from 0.490 0 to 0.919 3; the average value of genetic distance was 0.370 3, ranged from 0.086 3 to 0.713 4. And according to the UPGMA cluster analysis, the 93 samples could be obviously divided into five main groups based on genetic distance(D=20), When the genetic distance value was set at 15(D=15), the fifth group(including 77 germplasm)could be divided into 16 sub-groups. UPGMA clustering results indicated that most of the collections could be grouped upon their original geographic sites to be selected; even those relationships between germplasm classification and geographic origin would be very complicated.