Constitutive heterochromatin were studied in two Cyprinids Acanthobrama marmid and Cyprinion macrostomus in Turkey. The C-band patterns of the metaphase chromosomes of these species were reported. Diploid chromosome number was 2n=50 in all specimens. The C-bands were seen in the pericentromeric regions of all chromosomes in both species. In addition C-bands were observed on the short arms of two pairs of submetacentric chromosomes of A. marmid and on the short arms of two pairs of submeta-subtelocentric chromosomes of C. macrostomus. There were similarities between C-band blocks and NOR regions. C-band patterns were also similar in both species.