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The continuous Cenozoic strata are well outcropped in the Mazar Tagh, the central Tarim basin and the Quaternary are mainly thin lacustrine sediments, which are perfect basis of paleoclimate and paleoenvironment researches. A total of more than two hundreds of bulk samples were collected from the similar to 140m long sedimentary section. Here the result of field survey together with oxygen and carbon stable isotopic data is given; the paleoenvironment variation and its tectonic significances are also introduced. The Mid-Pleistocene climate transition is characterized by significant sediment assemblage change and drastically fluctuated stable isotopic data. Near the top of the section, the pronounced positive delta(13)C drift and negative delta(18)O excursion might indicate a extreme climate change and possible increasing influence of ice-snow melting water. The widely developed Quaternary lacustrine sediments in Mazar Tagh are distinctly different from the corresponding huge conglomerates and aeolian sandstone in the piedmont regions, which suggest the significant heterogeneity of regional tectonic activities. Acting as the front of the West Kunlun northern marginal thrust fault, Mazar Tagh fault might active in the Late Pleistocene or Holocene and currently remains active.