A data transmission method, comprising: receiving, by a target base station, first indication information from a terminal, wherein the first indication information is configured to indicate a number of packet data to be sent by the terminal and/or whether the packet data to be sent exists; and sending, by the target base station, first configuration information to the terminal, wherein the first configuration information is used by the terminal to determine at least one uplink transmission resource corresponding to at least one of the packet data to be sent, wherein the step of receiving, by the target base station, the first indication information from the terminal comprises: receiving, by the target base station, a first preamble from the terminal on a first Physical Random Access Channel, PRACH, resource, wherein the first PRACH resource and/or the first preamble have/has an association relationship with the number of the packet data to be received from the terminal; and determining, by the target base station, the number of the packet data to be received from the terminal according to the first PRACH resource and/or the first preamble; wherein the method further comprises: sending, by the target base station, second configuration information to the terminal, wherein the second configuration information is used by the terminal to determine the association relationship between the number of the packet data to be sent to the target base station and the first PRACH resource and/or the first preamble; wherein the second configuration information is configured through a system broadcasting message or dedicated signaling. receiving, by a target base station, first indication information from a terminal, wherein the first indication information is configured to indicate a number of packet data to be sent by the terminal and/or whether the packet data to be sent exists; and sending, by the target base station, first configuration information to the terminal, wherein the first configuration information is used by the terminal to determine at least one uplink transmission resource corresponding to at least one of the packet data to be sent, wherein the step of receiving, by the target base station, the first indication information from the terminal comprises: receiving, by the target base station, a first preamble from the terminal on a first Physical Random Access Channel, PRACH, resource, wherein the first PRACH resource and/or the first preamble have/has an association relationship with the number of the packet data to be received from the terminal; and determining, by the target base station, the number of the packet data to be received from the terminal according to the first PRACH resource and/or the first preamble; receiving, by the target base station, a first preamble from the terminal on a first Physical Random Access Channel, PRACH, resource, wherein the first PRACH resource and/or the first preamble have/has an association relationship with the number of the packet data to be received from the terminal; and determining, by the target base station, the number of the packet data to be received from the terminal according to the first PRACH resource and/or the first preamble; wherein the method further comprises: sending, by the target base station, second configuration information to the terminal, wherein the second configuration information is used by the terminal to determine the association relationship between the number of the packet data to be sent to the target base station and the first PRACH resource and/or the first preamble; wherein the second configuration information is configured through a system broadcasting message or dedicated signaling. sending, by the target base station, second configuration information to the terminal, wherein the second configuration information is used by the terminal to determine the association relationship between the number of the packet data to be sent to the target base station and the first PRACH resource and/or the first preamble; wherein the second configuration information is configured through a system broadcasting message or dedicated signaling.