| Kunming Basin is the biggest cenozoic intermontane fault basin in Yunnan province, it is characterized by lacustrine sediments mainly consisting of detrital material of terrigenous origin. Based on its upgrowth character, Kunming basin can be divided into two sub-areas: south sub-area and north sub-area.Based upon the analysis of drilling lithology, sedimentary facies, sedimentary gyration, granularity, wave speed, dating data and sporopollen information in Kunming Basin, combining with the forefather datum and archaeomagnetism, the division evidence of Hthostratigraphy and chronostratigraphy is determined, the studies on the Quaternary stratigraphic division and correlation are carried out.Quaternary Hthostratigraphy in the study area in Kunming Basin can be divided into 4 units named Dianchi formation, Zhongying formation, Guandu formation and Haigeng formation. It is indicated that the Quaternary strata character in the south sub-area is different from the north: sediments in the south sub-area is major in lacustrine-alluvial facies, however, in the south sub-area it is major in alluvial-diluvial facies. The reason for the difference above is the scale and thickness of the hollow in the south area is much bigger and thicker than the north area in Kunming Basin.. Quaternary stratigraphic division and correlation in the two sub-areas is discussed in detail.According to the latest division scheme and criterion, based on 14C , OSL , TL dating data and sporopollen information obtained latestly, Quaternary in Kunming Basin was used to be divided into 4 parts including Lower-Pleistocene(Qp1), Mid-Pleistocene (Qp2), Upper-Pleistocene (Qp3) and Holocene (Qh). The Pleistocene/Pliocene boundary is fit lower to M/G resversal (2.6Ma B.P.);Qp2/Qp1 boundary locates at B/M resversal (0.78Ma B.P.);Qp3/ Qp2 boundary is 0.128 MaB.P, corresponding to the Blake event, and Qp /Qh boundary is 0.012 MaB.P., corresponding to the Gothenburg event.
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