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Lucaogou Formation is the main formation for tight oil exploration and development in Junggar Basin. In order to analyze the geological characteristics and distribution of favorable areas, the favorable areas were divided based on the analysis of organic matter type, total organic carbon(TOC) content, maturity, reservoir rock type and porosity and permeability, combined with the lower limit of reservoir formation and burial. The results show that the organic kerogen types of Lucaogou Formation are mainly type Ⅰ and type Ⅱ1, with TOC content ranging from 0. 16% to 13. 86%, average content above 3. 0%, and average content of calcareous mudstone is 3. 79% . The maturity of organic matter is between 0. 55% and 1. 35%, and the main body is more than 0. 8% . From west to east, the maturity of organic matter decreases gradually, and it has the characteristics of wide distribution and large thickness, including the upper and lower two “source sweet spots”, and the thickness of “the lower sweet spot” is larger than “the upper sweet spot”. Reservoir rock types are diverse, high-quality reservoirs are concentrated in transitional rocks, dolomitic siltstone is the main reservoir rock type, and the pore structure is dominated by fine pore throats, which are typical low porosity and ultra-low permeability reservoirs. The porethroat connectivity is good, and the reservoir porosity-permeability correlation is good. Combined with the lower limit of tight oil accumulation depth, the favorable exploration areas of the first and second member of the Upper Lucaogou Formation are divided. The favorable exploration areas of the second member of the Lucaogou Formation are mainly distributed in well J32-H-J25-J32-J22 in the southeast of the sag, and the favorable exploration areas of the first member of the Lucaogou Formation are mainly distributed in well J251-J32-J174 in the middle and south of the sag. [ABSTRACT FROM AUTHOR]