Abstract: This paper deals with cytological study of seven populations in Paeonia delavayi var. lutea, which were collected from central to northwestern Yunnan. The chromosome num-ber in seven populations is 2n=10, and their karyotype asymmetries belong to is 2A type. Among populations, the second pair and the third pair of chromosomes are relatively stable, but there are some variations in the first pair and the fourth pair of chromosomes. There is structural heterozygosity in fourth pair of chromosomes. Both of relative length and arm ratio of homochromosome show structural heterozygositys. There may be a kind of correspondence between the sctructural heterozygosity of homochromosomes arid morphological difference. Among populations, the number and position of satellites have diffence, so do the number and position of the secondary constrictions.

Key words: P. delavayi var. lutea