Method for frequency measurement, comprising: generating, by a first network device, indication information, wherein the indication information is used for indicating a terminal device to measure a first frequency at which a second network device is located, the first network device being a network device in a new radio, NR, system, and the second network device being a network device in a long term evolution, LTE, system; and transmitting, by the first network device, the indication information to the terminal device; wherein the indication information is further used for indicating the terminal device to measure the first frequency according to a second measurement gap; characterized in that before generating indication information, the method further comprises: transmitting, by the first network device, a third message to the second network device, wherein the third message comprises a message, which is used for requesting the second network device to configure the second measurement gap for the terminal device; and receiving, by the first network device, a response message of the third message transmitted by the second network device, wherein the response message of the third message comprises the second measurement gap; and wherein generating indication information comprises: generating, by the first network device, the indication information according to the response message of the third message. generating, by a first network device, indication information, wherein the indication information is used for indicating a terminal device to measure a first frequency at which a second network device is located, the first network device being a network device in a new radio, NR, system, and the second network device being a network device in a long term evolution, LTE, system; and transmitting, by the first network device, the indication information to the terminal device; wherein the indication information is further used for indicating the terminal device to measure the first frequency according to a second measurement gap; characterized in that before generating indication information, the method further comprises: transmitting, by the first network device, a third message to the second network device, wherein the third message comprises a message, which is used for requesting the second network device to configure the second measurement gap for the terminal device; and receiving, by the first network device, a response message of the third message transmitted by the second network device, wherein the response message of the third message comprises the second measurement gap; and wherein generating indication information comprises: generating, by the first network device, the indication information according to the response message of the third message. transmitting, by the first network device, a third message to the second network device, wherein the third message comprises a message, which is used for requesting the second network device to configure the second measurement gap for the terminal device; and receiving, by the first network device, a response message of the third message transmitted by the second network device, wherein the response message of the third message comprises the second measurement gap; and wherein generating indication information comprises: generating, by the first network device, the indication information according to the response message of the third message.