A method for transmitting data, characterized by comprising: receiving, by a first network device, a first measurement result, wherein the first measurement result is used for indicating signal quality between a terminal device and the first network device and between the terminal device and a second network device respectively and used by the first network device to send a switch request to the second network device for requesting the second network device to switch the terminal device from the first network device to the second network device, and the first network device and the second network device belong to a first communication system; receiving, by the first network device, a second measurement result, wherein the second measurement result is used for indicating signal quality between the terminal device and a third network device and between the terminal device and a fourth network device respectively and used by the first network device or the second network device to determine whether to change the third network device and/or the fourth network device, the third network device and the fourth network device belong to a second communication system, and the first communication system is different from the second communication system, wherein the first communication system is long term evolution, LTE, and the second communication system is new radio, NR; wherein the switch request, sent by the first network device to the second network device, comprises the first measurement result and the second measurement result, and the first measurement result is used by the second network device to determine whether to switch the terminal device from the first network device to the second network device. receiving, by a first network device, a first measurement result, wherein the first measurement result is used for indicating signal quality between a terminal device and the first network device and between the terminal device and a second network device respectively and used by the first network device to send a switch request to the second network device for requesting the second network device to switch the terminal device from the first network device to the second network device, and the first network device and the second network device belong to a first communication system; receiving, by the first network device, a second measurement result, wherein the second measurement result is used for indicating signal quality between the terminal device and a third network device and between the terminal device and a fourth network device respectively and used by the first network device or the second network device to determine whether to change the third network device and/or the fourth network device, the third network device and the fourth network device belong to a second communication system, and the first communication system is different from the second communication system, wherein the first communication system is long term evolution, LTE, and the second communication system is new radio, NR; wherein the switch request, sent by the first network device to the second network device, comprises the first measurement result and the second measurement result, and the first measurement result is used by the second network device to determine whether to switch the terminal device from the first network device to the second network device.