Based on a large amount of data of core, log and seism, and using the newest methods of sedimentology, this paper clarified the characteristics of sedimentology of Yingcheng Formation in western fault basins belt of North Songliao Basin. There are fan delta depositional system, lacustrine and lake-floor fan system and also volcanic facies developed in the fault basins. Fan delta depositional systems were developed along the margin fault; toward the basin, lacustrine system was developed, specially, deep lak...