Aneuploidy is a well known chromosomal abnormality, and it is considered as a major cause of congenital birth defects and miscarriage. The present study aims to examine micronucleus frequency (MN), oxidative stress and antioxidant activity in chromosomal aneuploidy disorders including Down syndrome (DS), Klinefelter (KF) and Turner syndrome (TS), comparing to healthy controls matched age group. Peripheral blood samples were collected from 50 subjects, including, 20 normal healthy control and 30 patients with Down, Klinefelter and Turner syndromes. Micronucleus level was scored for each subject. Biochemical parameters, including lipid peroxide (LPO), nitric oxide (NO), total antioxidant capacity (TAC) were determined .The activity of paraoxonase1 (PON1) was also detected in blood serum for the three genetic diseases. DS and KF syndrome cases had an elevated count of MN (13.27 ± 0.59, 14.30±1.29 respectively vs. 1.80 ± 0.19; P < 0.05). However, Turner patients recorded an insignificant change in micronucleus frequency. In addition, significant decrease in TAC and PON1 was recorded in all patients comparing with normal controls (p≤0.05). While, NO and MDA product declared significant increase in DS, KF and Turner syndrome as compared to normal control group. Thus, it could be concluded that the MN, antioxidants and oxidative stress biomarkers assays are a powerful tools for detecting genetic disorders in chromosomal aneuploidy patients.