The present application discloses a data transmission method, including: configuring, by a first network element, a Packet Data Convergence Protocol (PDCP) reordering time for a terminal; sending, by the first network element, the PDCP reordering time of the terminal to a second network element; sending, by the first network element, a PDCP data packet of the terminal to the second network element, where the PDCP reordering time of the terminal is used to determine a transmission priority of the PDCP data packet of the terminal on the second network element. According to embodiments of the present application, a data packet loss can be reduced.