Abstract：The results of new regional survey has validated the sequence of the Paleoproterozoic Liaohe Group established in eastern Liaoning in the 1970s and the existence of the N-S facies change in the Liaohe Group. The Liaohe Group has all crossed the Yalu River and is distributed over various parts of the Langlin massif. Most of the Langlin Group is equivalent to the Liaohe Group. The main part of the original sedimentary basin of the Liaohe Group occurs as an E-W-trending narrow stripe. It takes the Archean continental crust as the base; in the basin bimodal volcanic rocks are developed. The tectonic attribute is the continental rift. In a few individual central parts, there appears oceanic crust separated from the massif. The paper also discusses the cause for the difference in geology between the northern and southern Archean continental blocks of the ancient basin.