A systematic study of C and O isotopic compositions was conducted for the Shennongjia Group (1.4~1.0 Ga) in the northern margin of the Yangtze Craton, yielding a total of 912 valid data of C and O isotopic compositions. The lithological characteristics and C and O isotopic compositions of the Shennongjia Group are of the important significance for understanding the sedimentary environment. The δ13CV- PDB of the Shennongjia Group varies from -2.20 ‰ to +6.27 ‰ with an average of +0.93‰ and The δ18OV- PDB ranges from -9.95 ‰ to ~-1.17 ‰ with an average of -4.95 ‰, which suggests that the Shennongjia Group can be generally attributed to facies of carbonate platform, platform margin and frontplatform slope surrounding tidal flat. Correspondingly, the relatively deep water period might occur in the Dayanping period, while the shallowest in the Luanshigou and Shicaohe periods. The δ13CV- PDB of the Shennongjia Group ranges primarily from -1.50‰ to +5.00‰, among which the lower subgroup has a broader shift range than that of the upper subgroup. The Shennongjia Group differ significantly from the Mesoproterozoic strata of the Jixian Section in the northern margin of the North China Craton in terms of C isotopic composition; both of them might be the counterparts of the Middle Riphean and Lower Riphean in the Southern Ural respectively. Comparison between Shennongjia Group and global C isotopic evolution curve indicates that the maximum depositional age of the lower subgroups of the Shennongjia Group should be less than ~1350 Ma. The upper subgroup of the Shennongjia Group are similar to the Bylot Supergroup of North American and the Atar Supergroup of West African in δ13C fluctuation range and trend that has an abrupt negative δ13CV- PDB excursion between 1.2 Ga and 1.1 Ga, which may be a response to the assembly event of the Rodinia supercontinent.