An out-of-synchronization determining method and apparatus are provided. The method includes: receiving, by a control network element, interference metrics sent by N base stations; determining, by the control network element based on the interference metrics, M first to-be-inspected base stations in the N base stations and/or neighboring stations of the N base stations; determining, by the control network element, P second to-be-inspected base stations, where the P second to-be-inspected base stations are base stations meeting a detection condition that are selected from the M first to-be-inspected base stations, and the detection condition is that a characteristic sequence broadcast by the first to-be-inspected base station at a specified position in a radio frame is not received by any neighboring station at the specified position; and determining, by the control network element, an out-of-synchronization base station in the P second to-be-inspected base stations.