A measurement configuration determining method, comprising: receiving, by a terminal device, a first message from a network device, wherein the first message comprises a first relationship, the first relationship is used to indicate an association relationship between an index of a reference signal and measurement configuration information, and the measurement configuration information is used by the terminal device to perform measurement; and determining, by the terminal device based on a first index corresponding to the terminal device, that measurement configuration information corresponding to the terminal device is first measurement configuration information having an association relationship with the first index, wherein the first index is an index of a reference signal corresponding to the terminal device, wherein the first measurement configuration information is in an active state, and measurement configuration information that is in the first relationship and that has no association relationship with the first index is in an inactive state, wherein the terminal device performs measurement based on the measurement configuration information in the active state, and does not perform measurement based on the measurement configuration information in the inactive state; either independently determining, by the terminal device, that the index of the reference signal corresponding to the terminal device is changed from the first index to a second index; and activating, by the terminal device, second measurement configuration information that has an association relationship with the second index based on the first relationship, and deactivating the first measurement configuration information; or receiving, by the terminal device, a third message from the network device, wherein the third message is used to indicate the second index, and the second index is an index of a corresponding reference signal obtained after the terminal device moves; and activating, by the terminal device, the second measurement configuration information that has an association relationship with the second index based on the first relationship, and deactivating the first measurement configuration information. receiving, by a terminal device, a first message from a network device, wherein the first message comprises a first relationship, the first relationship is used to indicate an association relationship between an index of a reference signal and measurement configuration information, and the measurement configuration information is used by the terminal device to perform measurement; and determining, by the terminal device based on a first index corresponding to the terminal device, that measurement configuration information corresponding to the terminal device is first measurement configuration information having an association relationship with the first index, wherein the first index is an index of a reference signal corresponding to the terminal device, wherein the first measurement configuration information is in an active state, and measurement configuration information that is in the first relationship and that has no association relationship with the first index is in an inactive state, wherein the terminal device performs measurement based on the measurement configuration information in the active state, and does not perform measurement based on the measurement configuration information in the inactive state; either independently determining, by the terminal device, that the index of the reference signal corresponding to the terminal device is changed from the first index to a second index; and activating, by the terminal device, second measurement configuration information that has an association relationship with the second index based on the first relationship, and deactivating the first measurement configuration information; or receiving, by the terminal device, a third message from the network device, wherein the third message is used to indicate the second index, and the second index is an index of a corresponding reference signal obtained after the terminal device moves; and activating, by the terminal device, the second measurement configuration information that has an association relationship with the second index based on the first relationship, and deactivating the first measurement configuration information.