The present disclosure provides a data packet transmission method and a device. The method includes: performing, by a transmit end device, channel coding on a to-be-sent data packet, and dividing the coded data packet into at least two data sub-packets; allocating a transmission resource to each data sub-packet; generating control information for each data sub-packet according to transmission resources of the at least two data sub-packets; and sending each data sub-packet and the control information of the data sub-packet on a corresponding transmission resource. A data packet and control information indicating a transmission resource of a data sub-packet are transmitted simultaneously, so that a receive end device can recognize multiple transmissions of a same data packet, and perform joint processing on multiple data sub-packets corresponding to the same data packet to obtain the sent data packet, and data packet transmission reliability is improved.