Background: Angiogenesis provides the oxygen and nutrients needed for metastasis and tumor growth, so by inhibiting angiogenesis, metastasis to other parts of the body can be prevented at the first steps of cancer. 5-Fluorouracil (5-FU) as a common chemotherapy drug and Quercetin as a natural compound both have anti-angiogenic properties. Objectives: In the current study improvement of the anti-angiogenic property of 5-FU by combination with quercetin was investigated. Methods: After treating the cells with alone or a combination of drugs the angiogenesis, vascular endothelial growth factor receptors (VEGFRs) gene expression, migration, and viability of the cells were evaluated using chicken chorioallantoic membrane (CAM) assay, real-time RT-PCR, wound healing and MTT assay, respectively. Results: Treatment with alone 5-FU and Que led to a significant reduction in angiogenesis, VEGFR2 and VEGFR1gene expression, migration, and Cell viability. The reductions were significant in the combination state compared to alone treatment. Conclusions: The results showed that the combination treatment with Que with 5-FU enhances the anti-angiogenic property of 5-FU, so it can be proposed as a potential anti-angiogenic and as a result anti-metastatic treatment for future animal studies. [ABSTRACT FROM AUTHOR]