〔Abstract〕 Objective To study the effect and mechanism of miR-301 a-3 p in exosomes secreted by osteosarcoma on the invasion of osteosarcoma U2-OS cells and the angiogenesis of vascular endothelial cells. Methods Immunofluorescence staining was used to detect whether exosomes could enter HUVEC to play a role.Western blot method was used to detect the effect of miR-301 a-3 p on the expression of vascular-associated proteins CD31,α-SMA and signaling pathway proteins, and the invasion experiment was used to detect the effect of miR-301 a-3 p on the invasiveness of OS cells. Results The exosomes secreted by U2-OS cells successfully entered HUVEC to play a role.Vascular-associated proteins CD31 and α-SMA were highly expressed, PI3 K/Akt, Mek/Erk pathway proteins were all highly expressed, and blood vessel growth ability relatively increased compared with the control group.After miR-301 a-3 p treatment, the invasion ability of U2-OS cells increased. Conclusion miR-301 a-3 p in osteosarcoma-derived exosomes may promote the invasion ability of U2-OS cells and the angiogenesis of HUVEC through PI3 K/Akt and Mek/Erk signaling pathways.