In recent years, Lucaogou Formation of Jimusar sag in Junggar Basin is one of the hotspots of exploration and development of tight sandstone oil reservoirs in China. Based on the analysis of main rock types of Lucaogou Formation, we use the cores, thin section, well logging and seismic data to comprehensively study on the sedimentary evolution, sequence stratigraphic framework, and the changes of sedimentary environment of the Lucaogou Formaiton. The study shows that the lithology of Lucaogou Formation is mainly composed of clastic rock and carbonate rock composition. The clastic rocks are mainly shale and siltstone（fine）sandstone, the carbonate rocks are mainly dolomite and limestone. The study of sedimentary characteristics shows that the lower, middle and upper parts of the mud shale segment were mainly developed in semi-deep-deep lake facies in the period of lake transgression, and the shale and mud are the main hydrocarbon source rock. The lower and upper parts of the tight sandstone were developed in the shallow lake facies and delta-front facies in the period of lake regression. Due to the late regional uplift, the sedimentary environment of Lucaogou Formation is gradually changed from the early open lake to the later limited lake, and this is also along with sedimentary water becoming more the salty and reductive.