The sampling scheme of core germplasm of local rice varieties of 6121 accessions catalogued in the national genebank,and
31 characters including taxonomic character,morphological character and yield character was studied,Sampling schemes were extablished at three levels,i.e.grouping principle,sampling
proportion within each group and sampling method within each group.Grouping principles used were Dingying's taxonomic system,Cheng Wang taxonomic system,Yunnan rice ecological zone,Yunnan administrative district,single character and completely random without grouping.Decision on sampling proportion within each group was based on square root,logarithm,index of
genetic diversity and simple proportion.Cluster and random were carried out for sampling in each group.The result showed that five parameters,index of genetic diversity, variance of phenotype value, variance of phenotypic frequency,coefficient of variation and ratio of phenotype retained in core sample,were used to test the validity of sampling scheme.The better sampling strategies were grouping principles based on two taxonomic systems,decisions on sampling proportion within each group based on square root and logarithm,sampling method within each group based on cluster.