Abstract: The comprehensive analyses of the sedimentary systems and synsedimentary faults in the 1st member of the Liushagang Formation in the Fushan Sag were made based on high-resolution sequence stratigraphy, sedimentology and structural geology. 3 sedimentary systems were concluded including braided river delta, fan delta and lacustrine sedimentary system. 9 sedimentary microfacies were classified. The synsedimentary systems in the 1st member of the Liushagang Formation in the Yongan-Bailian areas of the Fushan Sag were divided into the western extending accommodation fault system, the eastern strike-slip accommodation fault system and the central transfer fault system. The differential activities of the faults on each side of the central transfer fault system resulted in the migration of formation thickness center, migrating from west to east in the 1st member of the Liusha-gang Formation. The space-time evolution regularities of sedimentary systems indicated that the main delta sand body also migrated from west to east in the 1st member of the Liushagang Formation. The development of synsedimentary faults controlled the distribution of sedimentary systems and 3 controlling patterns were concluded.