This paper discusses the basic principle of continental sequence division. The authors suggest that the stratigraphic base level is a unifying concept in analysis of continental sequences and the base level transit cycle is control of the change of accommodation as well as distribution of major sequences. According to the development characteristics of the terrigenous successions, the conti- nental sequences can be divided into five orders; the basin-fill sequence, tectonic sequence, sequence, subsequence and microsequence. They are interpreded to be formed during the time-intervals of 60-120 Ma, 20-40 Ma, 0. 5-5 Ma, 0. 1-0. 5 Ma and <0. 1 Ma respectively, representing different ranks of base level transit cycles. Based on the general characteristic that the internal textures of continental depositonal sequences are controlled by the transit cycles, two system tracts can be easily idenfied, i. e. the system tract of base level rise and systems tract of base level fall. According to the above-mentioned principle the authors divide the Cretaceous System in Jiangsu into three tectonic sequences and the Middle Cretaceous Gecun Formation into five depositional sequences.