Abstract: The Silurian strata in Ningqiang,Shaanxi and Guangyuan,Sichuan on the western margin of the Yangtze platform are re-examined with the aid of the principles and methods of sequence stratigraphy,and grouped into nine third-order sequences,in which the transgressive and highstand systems tracts are developed but the lowstand and shelf-margin systems tracts are lacking.The Silurian sequence stratigraphic framework and sea-level curves are thus constructed on the basis of the sequence correlation in the study area.