Objectives: Suganhu area is located to the north side of Qaidam Basin, two areas separated by Saishiteng Mountain and Xiaosaishiteng Mountain. Drilling and outcrop data confirmed that the Jurassic below the Cenozoic of Suganhu area and Northern Qaidam Basin has a large distribution area, but the study on the Jurassic original sedimentary relationship between two areas is insufficient. Methods:In this paper, a comprehensive study based on the comparative analysis of stratigraphy and sedimentology, characteristics of later stage reconstruction and provenance analysis.Results:The study shows that the Jurassic in Suganhu area and Northern Qaidam Basin is comparable in lithology and sedimentary characteristics. In addition , these strata had been modified after Jurassic period, and the initial uplift of Saishiteng Mountain was in late Cretaceous ,forming the distribution of residual Jurassic now.Conclusions:The sedimentary scop in Suganhu area was small during the early Jurassic，therefore ,the sedimentary depression of Northern Qaidam and Suganhu area should be independent, and the study area is dominated by the faulted basin.In the Middle Jurassic period, Suganhu area and Northern Qaidam Basin were connected , Saishiteng area was deposited simultaneously，the whole study area was a depression type sedimentary basin of which the sedimentary scop was wider than the distribution of residual Jurassic now. The research results are of great significance for understanding Mesozoic—Cenozoic tectonic evolution and hydrocarbon resource evaluation and exploration deployment in the northern margin of Tibetan Plateau.