Conventionally stained and C- banded karyotypes of Guenther's vole (Microtus guentheri), Major's pine vole (Microtus majori) and Common vole (Microtus arvalis) were studied from Turkey. Diploid chromosome numbers of M. guentheri, M. arvalis and M. majori were found as 2n=54 and NFa=52, 2n=46 and NFa=68 and 2n=54 and NFa=56, respectively. All chromosomes of M. guentheri were pericentromeric C- band. In Microtus arvalis (obscurus cytotype) and Microtus majori karyotypes, autosomal chromosomes were heterochromatin C band positive and negative band. In M. arvalis (obscurus cytotype), sex chromosome was C band negative. In this study, heterozygote chromosome was not found in the obtained autosomal chromosome set of M. arvalis. M. majori has enlarged heterochromatin block from centromere to telomere on the long arm of X chromosome. Y chromosome was completely heterochromatin.