A method for transmitting data, comprising: acquiring, by a terminal device, first transmission control information of each network device in a plurality of network devices, wherein first transmission control information of a first network device in the plurality network devices is used for indicating that a state of a data duplication and transmission function configured by the first network device for a first data radio bearer, DRB, is an active state, and first transmission control information of a second network device except the first network device in the plurality of network devices is used for indicating that a state of the data duplication and transmission function configured by the second network device for the first DRB is an inactive state; and determining, by the terminal device, a target network device used for controlling the data duplication and transmission function of the first DRB as the first network device according to the first transmission control information of the each network device, characterized in that the method comprises: after the terminal device determines that the target network device used for controlling the data duplication and transmission function of the first DRB is the first network device according to the transmission control information of the each network device, the method further comprises: acquiring, by the terminal device, second transmission control information of the first network device, wherein the second transmission control information is used for indicating a state of the data duplication and transmission function configured by the first network device for the first DRB; and controlling, by the terminal device, the data duplication and transmission function of the first DRB according to the second transmission control information. acquiring, by a terminal device, first transmission control information of each network device in a plurality of network devices, wherein first transmission control information of a first network device in the plurality network devices is used for indicating that a state of a data duplication and transmission function configured by the first network device for a first data radio bearer, DRB, is an active state, and first transmission control information of a second network device except the first network device in the plurality of network devices is used for indicating that a state of the data duplication and transmission function configured by the second network device for the first DRB is an inactive state; and determining, by the terminal device, a target network device used for controlling the data duplication and transmission function of the first DRB as the first network device according to the first transmission control information of the each network device, characterized in that the method comprises: after the terminal device determines that the target network device used for controlling the data duplication and transmission function of the first DRB is the first network device according to the transmission control information of the each network device, the method further comprises: acquiring, by the terminal device, second transmission control information of the first network device, wherein the second transmission control information is used for indicating a state of the data duplication and transmission function configured by the first network device for the first DRB; and controlling, by the terminal device, the data duplication and transmission function of the first DRB according to the second transmission control information. acquiring, by the terminal device, second transmission control information of the first network device, wherein the second transmission control information is used for indicating a state of the data duplication and transmission function configured by the first network device for the first DRB; and controlling, by the terminal device, the data duplication and transmission function of the first DRB according to the second transmission control information.