The Middle Permian Pingdiquan Formation in the piedmont depression of Kelameili Mountain in eastern Junggar Basin is equivalent to Lucaogou Formation and Hongyanchi Formation in the piedmont depression of Bogda Mountain. Lucaogou Formation and Pingdiquan Formation are important series of strata with source rocks. The isochronous stratigraphic framework of Lucaogou Formation and Pingdiquan Formation has not been established，which affects the distribution range of source rocks in horizontal and vertical directions. According to the systematic analysis of well seismic，outcrop and geochemical data，this paper divides the sequence stratigraphic units of Lucaogou Formation and clarifies the corresponding relationships with Pingdiquan Formation. Moreover，the paper establishes the sedimentary filling models of Lucaogou Formation in eastern Junggar Basin. The results show that the middle Permian Lucaogou Formation and Hongyanchi Formation on the periphery of Bogda Mountain are both third-order sequences，respectively corresponding to the third-order sequence1 at the lower part of Pingdiquan Formation and the third-order sequence 2 at the upper part.Lucaogou Formation（Sequence1）develops lowstand，transgressive and highstand system tracts. The lowstand system tract is dominated by fan delta，delta and shore-shallow lake deposits，and the semi-deep lake-deep lake facies is only distributed in Bogda area. The distribution ranges of semi-deep lake-deep lake facies in the transgressive system tract reach the maximum in each sag.The scales of fan delta，delta and turbidite fan sand bodies in the highstand system tract increase，and the distribution ranges of semi-deep lake-deep lake facies decreases. During the sedimentary period of transgressive and highstand system tracts in Lucaogou Formation，the semi-deep lake-deep lake facies developed high-quality source rocks，which formed a good source-reservoir assemblage with various types of sand bodies in the highstand system tract. The highstand system tract of Lucaogou Formation is favorable exploration strata of Middle Permian in eastern Junggar Basin.