Embodiments of this application disclose a data transmission method, a related apparatus, and a device. The method is applied to the communication field, to improve reliability of data transmission and reduce a delay of data transmission. In the method in embodiments of this application, a transmit end device obtains a plurality of pieces of packet data in a transmission sequence and encapsulates the plurality of pieces of packet data in the transmission sequence, to obtain N pieces of encapsulated packet data, and sends the plurality of pieces of encapsulated packet data to a receive end device in the transmission sequence through a plurality of communication links. In this way, the receive end device can receive, through the communication links, the plurality of pieces of encapsulated packet data sent by the transmit end device and perform unpacking processing on the plurality of pieces of encapsulated packet data, to obtain the plurality of pieces of packet data and packet sequence numbers of the plurality of pieces of packet data, determine the transmission sequence based on the packet sequence numbers of the plurality of pieces of packet data, and send the plurality of pieces of packet data in the transmission sequence. N is greater than or equal to 2.