A channel state information, CSI, measurement method, comprising: obtaining, by a first network device, CSI configuration information that comprises first frequency-domain indication information and that is sent by a second network device, wherein the CSI configuration information is used to instruct the first network device to perform CSI measurement, and the first frequency-domain indication information is used to indicate a frequency-domain location in which the first network device performs CSI measurement; and measuring, by the first network device based on the CSI configuration information, a reference signal in the frequency-domain location indicated by the first frequency-domain indication information, to obtain CSI, wherein the reference signal includes a channel measurement reference signal and/or an interference measurement reference signal, wherein the first frequency-domain indication information comprises channel bandwidth division information, and the channel bandwidth division information is used to indicate a manner of dividing channel bandwidth into a plurality of resource blocks, wherein the first frequency-domain indication information comprises a frequency-domain measurement identifier corresponding to each of the plurality of resource blocks of the channel bandwidth; and the measuring a reference signal in the frequency-domain location indicated by the first frequency-domain indication information comprises: obtaining, by the first network device, the frequency-domain measurement identifier corresponding to each of the plurality of resource blocks of the channel bandwidth, wherein the frequency-domain measurement identifier comprises a first measurement identifier and a second measurement identifier; and measuring, by the first network device, a reference signal on a resource block whose frequency-domain measurement identifier in the channel bandwidth is the first measurement identifier. obtaining, by a first network device, CSI configuration information that comprises first frequency-domain indication information and that is sent by a second network device, wherein the CSI configuration information is used to instruct the first network device to perform CSI measurement, and the first frequency-domain indication information is used to indicate a frequency-domain location in which the first network device performs CSI measurement; and measuring, by the first network device based on the CSI configuration information, a reference signal in the frequency-domain location indicated by the first frequency-domain indication information, to obtain CSI, wherein the reference signal includes a channel measurement reference signal and/or an interference measurement reference signal, wherein the first frequency-domain indication information comprises channel bandwidth division information, and the channel bandwidth division information is used to indicate a manner of dividing channel bandwidth into a plurality of resource blocks, wherein the first frequency-domain indication information comprises a frequency-domain measurement identifier corresponding to each of the plurality of resource blocks of the channel bandwidth; and the measuring a reference signal in the frequency-domain location indicated by the first frequency-domain indication information comprises: obtaining, by the first network device, the frequency-domain measurement identifier corresponding to each of the plurality of resource blocks of the channel bandwidth, wherein the frequency-domain measurement identifier comprises a first measurement identifier and a second measurement identifier; and measuring, by the first network device, a reference signal on a resource block whose frequency-domain measurement identifier in the channel bandwidth is the first measurement identifier. obtaining, by the first network device, the frequency-domain measurement identifier corresponding to each of the plurality of resource blocks of the channel bandwidth, wherein the frequency-domain measurement identifier comprises a first measurement identifier and a second measurement identifier; and measuring, by the first network device, a reference signal on a resource block whose frequency-domain measurement identifier in the channel bandwidth is the first measurement identifier.