Abstract: The Neoproterozoic stratigraphy of South China records important information about global glacial events, the Rodinia supercontinent rifting and early life evolution. However, its depositional age and regional stratigraphic comparison remain controversial. This study focuses on the geochronology of Neoproterozoic Shenshan and Shangshi Formations in the central Jiangxi of South China by means of zircon LA-ICP-MS U-Pb dating on tuffaceous siltstone to constrain the depositional age of these stratigraphic units and facilitate their regional stratigraphic correlation. The study shows that zircon ²⁰⁶Pb/²³⁸U weighted mean ages of (805 ± 6) Ma was obtained from tuffaceous siltstone layers in the middle Shenshan Formation, which limits the depositional age of the central Shenshan Formation at ca. 830–800 Ma,while that in the middle and lower Shangshi Formation is (769 ± 6) Ma,corresponding to the depositional age of ca. 770–720 Ma. Furthermore, the comparison of these isotopic ages indicate an isochronal stratigraphic framework between the Shenshan Formation and the Jialu Formation (the age is (815 ± 6 ) Ma) and the Cangshuipu Formation(the age is (821 ± 13) Ma）of the Xiajiang Group, the Hetong Formation(the age is (801 ± 4) Ma), Wuqiangxi Formation (the age is (809 ± 9) Ma) and the Panzhao Formation (the age is (802 ± 2) Ma)of the Danzhou Group in the Yangtze Block. The Shangshi Formation geochronologically corresponds with the Shangshu Formation (the age is (767 ± 5) Ma) of the Heshangzhen Group, the Qingshuijiang Formation (the age is (764 ± 6) Ma), and the Liantuo Formation (the age is (763 ± 10) Ma and (767 ± 3) Ma) in the Yangtze Block. This study provides additional geochronological evidence for the correlation of Neoproterozoic strata between the Yangtze and Cathaysia Blocks.