Background: Acute lymphoblastic leukemia (ALL) is most common in childhood. Inhibin (a non-steroidal glycoprotein hormone of gonadal origin) can be used as marker of fertility. The current study was conducted to evaluate inhibin levels in ALL patients and to estimate its correlation with some antioxidants in these in comparison with control subjects. Materials and Methods: This study was conducted on sixty patients with ALL and thirty children as controls. Fasting blood samples were taken from each subject and analyzed for haemoglobin, serum protein, vitamin E and C, in addition to glutathione and inhibin. Results: The results of the study showed highly significant decreases (p<0.001) in haemoglobin, glutathione and inhibin levels with significant decreases (p<0.05) in serum protein and vitamin E levels for patients group in comparison with controls while there was no significant differences in vitamin C. Moreover, there were significant correlations between inhibin levels and serum protein, glutathione and both vitamins (E and C) in the ALL patient group (r= 0.81, 0.80, 0.77 and 0.69, respectively). Conclusions: The present results indicated infertility in patients with ALL demonstrated by low inhibin level as a consequence of abnormality in anti-oxidative metabolism due to the cancer process. So, it can be suggested the need for routine measurement of inhibin for leukemic patients to estimate the action of hormones of gonadal origin.