Abstract: The conventional karyotype,C-banding and Ag-NORs of four rhacophorid tree frog species (Those are Polypedates nigropunctatus,P.omeimontis,P.mutus and Rhacophorus feae) from Yunnan Province have been studied using the bone marrow preparing chromosome.Results showed that the same diploid number (2n=26) and karyotypic formular they have,except for P.mutus that have 6+7 formular,but the number and sequence of the submetacentric chromosome,secondary construction (SC) or the satellite and Ag-NORs are different each other.In P.nigropunctatus Nos.3,12 are SM,Ag-NORs and SC localized on 10pinter.Nos.2,3,4,6,9 are SM and the satellite,Ag-NORs are on 12qter in P.omeimontis,without SM and on 6qinter of Ag-NORs in P.mutus,but in Rhacophorus feae the Nos.2,3,4 are SM,and two pairs Ag-NORs appeared on 12qter and 13qter.Meantimes the satellite association was found.All these species in which the C-positive mainly are on the centromeric regions of all chromosomes and the C-negative reaction always appeared on SC or Ag-ONRs locations.Finally the possible mechanism of karyotypic change among them have been discussed.