© 2019 by Türkiye Klinikleri.Objective: Aplastic anemia (AA) is a haematological disorder charecterized by pansi-topenia and hypocellular bone marrow without abnormal infiltration and no increase in reticulin. The disease may occur as congenital/inherited or acquired. In about 15% of patients with acquired AA, even after years of remission acquired with immunosuppressive therapies, bone marrow malignancies like myelodysplastic syndrome or acute myeloid leukemia (AML) appears. Cytogenetic studies on AA reveal structural and numerical abnormalities of different chromosomes in 12% of cases. The most common chromosomal abnormalities are deletion/monosomy of chromosome 7 and +8 in AA. 5q-,+6, t(8;21), deletion/monosomy of chromosome 13 and loss of Y chromosome are rarely observed.-7 is an indicator of poor prognosis, typically related with resistant cytopenia or AML. Good response to immunosuppressive therapies is reported with +8. Material and Methods: Cytogenetic abnormalities which were obtained by conventional karyotyping from bone marrow samples of 37 AA cases are presented. 24h and 48h culture and GTL banding were performed and, chromosomes were evaluated according to “International System for Human Cytogenomic Nomenclature 2016”. Results: 32% of the cases had abnormal karyotypes. Abnormalities observed in our cases were; only-17 in two cases each;,-7,+8,-9, +10,-10, +11,-14,-16, del (17) (q11q21),-19,-20,-21, del (22) (q13), inv(X)(p11p23), and loss of chromosome X and Y in one case each. In 5 cases tetraploid (±92) metaphases were observed. Conclusion:-7 and +8 that we observed in one cases each are known abnormalities as freqently seen in AA cases. And,-16, chromosome 17 abnormalities,-20, aneuploidies of X and Y were reported in literature before.