In this study, we investigated the effects of lentivirus (LV)-mediated short hairpin RNA (shRNA) targeting IGF-1R on the growth and lymphangiogenesis of breast cancer. The LV vector effectively delivered the IGF-1R shRNA to MDA-MB‑231 cells, leading to significant reduction of IGF-1R mRNA and protein expression. Infection of MDA-MB-231 cells with LV-IGF-1R shRNA reduced cell growth and migration. Transplantation of MDA-MB-231 cells with suppressed IGF-1R expression in SCID mice reduced tumor growth and lymphangiogenesis. These data collectively suggest that LV-mediated shRNA is an effective way to suppress IGF-1R expression and to inhibit growth and lymphangiogenesis of breast cancer. Specific inhibition of IGF-1R expression with shRNA represents a promising approach for the treatment of breast cancer.