Embodiments of the invention provide a
data transmission method and device. The method comprises the following steps that a
multicast transmission
control network element receives a first non-access layer message, wherein the first non-access layer message comprises receiving quality indication information of a terminal for receiving data on a
multicast transmission path; after the
multicast transmission
control network element receives the receiving quality indication information, the
multicast transmission control network element determines to start a
unicast transmission path; and the
multicast transmission control
network element sends a first indication message to a user plane
network element, wherein the first indication message is used for indicating to start a first
unicast transmission path, and the first
unicast transmission path is used for assisting the
multicast transmission path to transmit data to the terminal. Through the application of the embodiments of the invention,the data receiving quality indication information of the terminal can be obtained through the non-access layer message, and the unicast transmission path is used for assisting the multicast transmission path to transmit the data to the terminal, so that the
data transmission in a double-flow mode is realized, and the method and the device have the advantages that the reporting efficiency of the data receiving quality is improved, the
data transmission reliability is enhanced and the data transmission efficiency is improved.