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The Late Neoproterozoic to Early Cambrian is a remarkable time-interval that witnessed significant biolo-gical and environmental evolutions, during which, the deep ocean was extensively anoxic, whereas the surface ocean was characterized by considerable fluctuations in redox conditions. The Lower Cambrian Yanjiahe and Shuijingtuo formations in the Luojiacun section from the Three Gorges area situated in Yichang city of central China were studied in this paper. According to biostratigraphic and carbonate carbon isotope stratigraphic correlation, the Yanjiahe Formation and Shuijingtuo Formation were assigned to the Cambrian Terreneuvian Stage 1-2 and Series 2 Stage 3, respectively. In view of this time-frame, the response of inorganic and organic carbon isotopes decoupling to water redox environment transition was systematically studied. The rise of anoxic bottom water during transgression provided sufficient nutrients and essential trace elements for primary productivity in the surface ocean. The increase of net productivity led to oxygen consumption increase and the changes of redox environment in the water column. Photosynthetic oxygen temporarily oxygenated the surface seawater, and dissolved oxygen was gradually consumed by the oxidation of DOC reservoirs, resulting in gradual expansion of oceanic anoxia, which was conducive for the preservation of organic matters. The oxidation of DOC in the surface water accounted for the formation of authigenic carbonates that were 13C-depleted, while the large oceanic DOC reservoir in the Early Cambrian buffered the change in δ13Corg, which eventually manifested as decoupled carbon isotope during the transition time of Cambrian Stage 2-3.