A data transmission method, comprising: receiving, by a terminal device, feedback configuration information from a network device, wherein the feedback configuration information is used to indicate a configuration of feedback information specific to uplink data of the terminal device; sending, by the terminal device, the uplink data to the network device; and determining, by the terminal device in a feedback message sent by the network device, the feedback information to the uplink data based on the feedback configuration information; wherein the feedback configuration information comprises a feedback time interval of the feedback information, a quantity of bits occupied by the feedback information in the feedback message, and a location index of the feedback information in the feedback message, wherein the feedback time interval represents a time interval between sending the uplink data and receiving the feedback information by the terminal device, and the location index represents a start bit location of the feedback information of the terminal device in the feedback message; wherein before the sending, by the terminal device, the uplink data to the network device, the method further comprises: receiving, by the terminal device, activation instruction information from the network device; and activating, by the terminal device according to the activation instruction information, the configuration indicated by the feedback configuration information; wherein the feedback message is specifically common downlink control information, Common DCI, wherein the Common DCI is DCI specific to a plurality of terminal devices, and one piece of Common DCI includes information specific to the plurality of terminal devices. receiving, by a terminal device, feedback configuration information from a network device, wherein the feedback configuration information is used to indicate a configuration of feedback information specific to uplink data of the terminal device; sending, by the terminal device, the uplink data to the network device; and determining, by the terminal device in a feedback message sent by the network device, the feedback information to the uplink data based on the feedback configuration information; wherein the feedback configuration information comprises a feedback time interval of the feedback information, a quantity of bits occupied by the feedback information in the feedback message, and a location index of the feedback information in the feedback message, wherein the feedback time interval represents a time interval between sending the uplink data and receiving the feedback information by the terminal device, and the location index represents a start bit location of the feedback information of the terminal device in the feedback message; wherein before the sending, by the terminal device, the uplink data to the network device, the method further comprises: receiving, by the terminal device, activation instruction information from the network device; and activating, by the terminal device according to the activation instruction information, the configuration indicated by the feedback configuration information; wherein the feedback message is specifically common downlink control information, Common DCI, wherein the Common DCI is DCI specific to a plurality of terminal devices, and one piece of Common DCI includes information specific to the plurality of terminal devices. receiving, by the terminal device, activation instruction information from the network device; and activating, by the terminal device according to the activation instruction information, the configuration indicated by the feedback configuration information; wherein the feedback message is specifically common downlink control information, Common DCI, wherein the Common DCI is DCI specific to a plurality of terminal devices, and one piece of Common DCI includes information specific to the plurality of terminal devices.