A data transmission method, performed by a receive end, includes: receiving notification information that is about to-be-transmitted data and that is sent by a transmit end, where the notification information includes a size of the to-be-transmitted data of the transmit end; generating a plurality of RDMA read requests based on the size of the to-be-transmitted data; and sending the plurality of RDMA read requests to the transmit end, where a bandwidth occupied by data read by the plurality of sent RDMA read requests is less than or equal to an ingress bandwidth of the receive end.