Abstract: On the basis of outcrops, cores and seismic data in this study and the previous data, the author in this study proposes a new shelf, i. e., the Jiannan shelf that represents the southeastward extended part of the Kaijiang-Liangping shelf penetrated from the Xuanhan-Daxian-Liangping-Kaijiang zone southeastwards to the Jiannan area during the Changxingian, and may be connected with West Hubei shelf in the east. Compared with the Kaijiang-Liangping shelf, the Jiannan shelf has the following features. (1) The Jiannan shelf is a shallow-water shelf. (2) The Jiannan shelf was initiated during the early-middle Changxingian and terminated due to the filling up during the late stages of the Changxingian. (3) The Jiannan shelf and its adjacent areas exhibit a carbonate ramp model in which the Changxingian bioherms occur as excellent dolostone reservoirs with good physical properties.