"nBackground: Vascular endothelial growth factor (VEGF) has mitogenic effect for endothelial cells and is an important mediator of tumor expansion, metastasis and angiogenesis in vivo. Isosorbide dinitrate, as a nitric oxide donor, has been widely used in treatment of many cardiovascular diseases such as congestive heart failure and acute coronary syndromes. Furthermore this drug was found to have inhibitory effect on angiogenesis, tumor growth and metastasis in vivo. In the present study we evaluated the isosorbide effect on the VEGF production using some human leukemic cell lines. "nMethods: Human leukemic MOLT-4, JURKAT and U937 cells were cultured in complete RPMI medium. The cells at the exponential growth phase were then incubated with different concentrations of Isosorbide (4′10-7 -4′10-4 M) in the presence or absence of PMA (25ng/ml) for 24 hours. The VEGF concentrations in the culture supernatants were measured by enzyme immunoassay kits (R&D systems) according to the manufacturer's instructions. "nResults: The level of VEGF produced by the human leukemic cell lines which was treated with different concentrations of isosorbide, did not show any significant difference with untreated control cells. "nConclusions: The results of this study showed that isosorbide had no significant effect on VEGF production. Our findings suggest that anti-angiogenesis effect of isosorbide could be mediated through VEGF-independent mechanism(s). Further studies are warranted to determine definite isosorbide effect on VEGF and other angiogenic factors production in patients as well as animal models.