Objective To determine the effect of insulin-like growth factor-1 (IGF-1) on angiogenesis in mouse breast cancer model of lower and normal serum IGF-1 levels after using angiogenesis inhibitor ginsenoside Rg3 (GS Rg3). Methods The breast cancer models were established in control mice and liver specific IGF-1 deficient (LID) mice by feeding DMBA and were treated with GS Rg3. Vascular endothelial growth factor (VEGF) and F8-RAg were detected by immunohistochemical method in breast cancer tissues. IGF-1 gene and angiogenesis relating genes were detected by gene chip in breast cancer and normal breast tissue. Results The incidence rate of breast cancer in LID mice was lower than that in control mice (P<0.05). VEGF expression and microvessel density of LID mice were lower than those in control mice (P<0.05). Compared to the control mice, IGF-1, FGF-1, TGF-β1 and HGF genes were increased, and FGFR-2, PDGF-A and PDGF-B genes were decreased in breast cancer of LID mice. After GS Rg3 treatment, VEGFa, EGF, EGFR, PDGF-A and FGFR-2 genes were increased, IGF-1 and TGF-β1 genes were decreased in breast cancer of LID mice compared with the control mice. Conclusion IGF-1 may be involved in mouse breast cancer progression and associated with the growth of blood vessels. Angiogenesis inhibitor may play an antitumor role by IGF-1 and TGF-β1.