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According to the assumption of "deposition control facies, facies control reservoir", based on field investigation, experimental test and previous research results, a study was performed to investigate the characteristics of shale reservoir controlled by the sedimentary environment of the Lower Cambrian Qiongzhusi Formation in the Middle Lower Yangtze area. The studies show that the organic-rich shale is mainly developed in the shelf facies and deep-sea retention basin facies, the thickness of deposition center is up to 100-180 m with the maximum organic carbon content of 18.7%, and the average organic carbon content is 5.07%. The major lithologies include organic-rich carboniferous shale, siliceous shale, silty shale and calcareous shale under anoxic environment. The minerals of the shale are mainly quartz (average 64.97%) and clays (average 23.66%). A large number of intergranular holes of pyrite under the anoxic environment, microporosity produced by hydrocarbon generation in organic matter, microporosity between layers of clay minerals and micro-cracks controlled by brittle mineral provide a good reservoir space for shale gas. Therefore, the studies on the development of reservoir characteristics under the control of the environment will provide a substantial basis for shale distribution, organic matter abundance, reservoir space and favorable area evaluation in shale gas exploration and development. [ABSTRACT FROM AUTHOR]