Neovascularization is often involved in many diseases and there is no effective treatment for this pathological process. In searching for potential therapies for neovascularization, we screened nineteen pre-selected small molecules isolated from herbal extracts for their possible anti-angiogenic effect in vitro and in vivo. We found that isoliquiritigenin, a chalconoid compound isolated from Chinese herb medicine licorice, potently inhibited vascular endothelial cell (EC) proliferation, migration, tube -like structure formation ex vivo. Western blot analysis shows that exposure of ECs to isoliquiritigenin inhibited extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. In Matrigel plug assay, isoliquiritigenin effectively blocked fibroblast growth factor-induced in vivo angiogenesis in mice. Consistently, topical application of isoliquiritigenin significantly inhibited chemical injury-induced corneal neovascularization in mice. Collectively, these results suggest that isoliquiritigenin may be a low-cost and effective natural agent to treat angiogenesis-dependent diseases.