The present invention relates to a security message transmission method and apparatus. The method includes: generating, by a vehicle terminal, a first security message, where the first security message carries message type information; adding priority indication information of the security message to a geographic information layer according to the message type information, and obtaining a second security message; determining, at a Media Access Control (MAC) layer, a transmission path of the security message according to the priority indication information; and sending the second security message to a recipient by using a physical layer corresponding to the determined transmission path, so that the recipient performs forwarding processing on the second security message. According to the present invention, a security message is forwarded to a vehicle terminal within a predetermined distance range in a manner of combining a VDC technology and an LTE cellular network.