There is mostly rough deep sea bottom topography on the northern slope of the South China Sea.All types of multiples are well-developed.Identification and suppression of multiple have always been the emphasis and difficulty in the area's seismic data processing.The selection of a suitable method from multiple attenuation techniques is the key to obtaining high quality imaging of seismic profile.Through the study of multiple in original seismic data of three lines located on the northern slope of the South China Sea from the east to the west,the authors analyzed the characteristics of various types of multiple,applied τ-p domain deconvolution prediction,SRME(Surface Related Multiple Elimination),high-precision Radon transform and frequency versus energy decay method to effectively suppress various types of multiple,thus making improvement of the quality and effects of composition and clarifying characteristics of reflected waves in the middle and deep layer.As a result,the distinction and explanation become easy.