Abstract: The basin fillings of Shahezi Formation(J₃sh) in Xinlicheng basin of the east margin of the Songliao demonstrates a transgressive-regressive process during which the different sequences including lake basin sequence and alluvial sequence(river basin sequence) developed at different stages. The lake basin sequence occurred in lake basin belonging to early stage of Xinlicheng basin's development and the alluvial sequence occurred in river basin belonging to later stage of that. The developments of those two types of sequences are the sedimentary and stratal response to the basin dynamics of the Songliao basin at rifting time.