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In order to further expand the exploration results of Cretaceous reservoirs in Kuqa Depression, clarify formation mechanism of reservoirs, based on data, such as drilling, logging, ordinary slice, casting thin sections, granularity analysis, X-ray diffraction analysis and physical properties, reservoir characteristics and controlling factors of Cretaceous Bashijiqike Formation in Kelasu structural belt and Qiulitage structural belt in Kuqa Depression of Tarim Basin have been systematically studied. The Cretaceous reservoirs in Qiulitage area are coarse in grain size, low in feldspar content, high in rock debris content especially in sedimentary rock debris; the content of interstitial material is slightly lower, the content of matrix is higher and the content of cement is lower; they have good physical properties and are low porosity and low permeability reservoirs with the characteristics of high displacement pressure, medium-small pore throat radius and fine - microfine throat; medium compaction, medium cementation and strong dissolution are beneficial to the preservation of reservoir pores. The Cretaceous reservoirs in Kelasu structural belt are fine in grain size, mainly composed of medium and fine sandstones, with high feldspar content and low rock debris content, and a few sedimentary rock debris; the total amount of interstitial material is slightly higher, the content of matrix is low, and the cementation is compact; surface porosity is generally low and microcracks are common; they have bad physical properties and are ultra-low porosity and ultra-low permeability reservoirs with the characteristics of high displacement pressure, extremely small pore throat radius and microfine throat; besides strong compaction, tight cementation and weak dissolution, though fractures have limited contributions to reservoir pores, they greatly improve reservoir permeability. [ABSTRACT FROM AUTHOR]