Abstract: Apparent frequency is an important information for seismic data interpretation.The analysis of the relationships between apparent frequency in the seismic profile and structural evolution,the sediment controlled by structure,denudation caused by tectonic uplift,violent degree of tectonic action in different times in the Wuerxun Sag of the Hailaer Basin,show that structural factor is one of the important factors that influence the change of apparent frequency on seismic profile.It affects the apparent frequency by controlling and reforming the sedimentary stratigraphic structure.The lateral abrupt change of apparent frequency on the seismic profile reflects faults and vertical abrupt change reflects tectonic unconformities,especially parallel unconformity based on some theories.