Through restoration, degraded wetlands are thought to recover their carbon storage function over time. However, little is known about the dynamics of soil organic carbon (SOC) and its fractions after restoration of degraded wetlands. In this study, we selected four wetlands, two degraded (one grazed and one graze-released site), one restored for 6 years and one natural site from the Zoige wetlands on the Qinghai–Tibetan Plateau, China to investigate the dynamics of SOC following restoration. The concentrations of SOC, dissolved organic carbon (DOC), light fraction organic carbon (LFOC), and heavy fraction organic carbon (HFOC) in the degraded sites were significantly lower than those in the natural wetland. In contrast, soil δ13C (i.e. 13C/12C ratio) in the degraded sites was significantly higher than that in the natural site. After 8 years of restoration, the restored and the natural wetland sites did not differ significantly in SOC, DOC, LFOC, HFOC or δ13C. Therefore, restored wetlands regained some of their role in carbon storage over time. SOC turnover was slower in the natural wetland than in the degraded and restored sites.