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The sequence stratigraphy of fine-grained sedimentary rocks (FGSR) is difficult topic but a development tendency.This paper puts forward the division method，formation constitutes and model of lacustrine FGSR.The division method includes two steps：Synthetically vertical division and horizontal comparison analysis.Firstly，based on lithofacies and its combination，mineral composition，and geochemical indicators，this paper determines the interface standard and method to divide systems tracts.Secondly，the division method of parasequence set and stratigraphic (lithofacies) pattern established a comparison with traditional sequence stratigraphy.At last，connecting-wells show that stratigraphic pattern，water body variation，and characteristics of interface of fine-grained sedimentary rocks are same with coarse sediments.Based on the above methods，typical well in Dongying Sag is chosen as a case to divide sequence stratigraphy of fine-grained sedimentary rocks.The results show that a whole third-order sequence was developed including lowstand system tract，lacustrine transgressive system tract (TST) and highstand system tract.There are two types in TST，lake surface passive rise and lake surface normal to rise.After vertical division and lateral comparison，sequence stratigraphy model is established.As the special nature of fine-grained sedimentary rocks，the development of sequence stratigraphy is affected by the climate more obviously. [ABSTRACT FROM AUTHOR]