[Objective] In order to scientifically evaluate the eco-environmental effects of inland degraded saline-alkali wetlands after restoration, and to analyze the changes of soil organic carbon content and reserves after restoration. [Methods] Selected typical marsh wetlands degraded for many years (alkali spot land, Leymus chinensis grassland) and flooded phragmites australis swamp land in the western part of Songnen Plain as study sample plots. Based on the measurement of aboveground-underground biomass, physical and chemical properties and nutrient content of 1 m underground soil profile, the changing rules and influencing factors of SOC content and storage in degraded saline-alkali wetland were analyzed and discussed. [Results] after restoration, the vegetation biomass and carbon pool of phragmites australis wetland were 8446.54 g·m-2 and 1.90 kg·m-2 respectively, which increased by 422.68% and 216.67% respectively compared with Leymus chinensis grassland. The vegetation biomass and carbon pool of alkaline spot land were 0, and those of Leymus chinensis grassland were 1616.00 g·m-2 and 0.60 kg·m-2, respectively. Flooded restoration of degraded wetlands promoted the increase of vegetation biomass and carbon storage. After restoration, the organic carbon storage in 1 m soil profile of phragmites australis marsh wetland was 17.38 kg·m-2, which was 64.12% and 4.45% higher than that in alkali spot land and Leymus chinensis grassland, 10.59 kg·m-2 in alkali spot land and 16.64 kg·m-2 in Leymus chinensis grassland. Flooded restoration of degraded wetlands promoted the increase of soil organic carbon storage. The content of soil organic carbon in the deep soil of the degarded and restored wetlands was higher than that in the surface layer, the growth of vegetation increased the content of soil organic carbon, and the gaps and flooding between soil particles promoted the migration of organic carbon to the deep layer. The content and storage of SOC were positively correlated with soil water content, and negatively correlated with total nitrogen, total phosphorus, electrical conductivity and the ratio of nitrogen to phosphorus. There were significant differences in soil physical and chemical properties among alkali spot, Leymus chinensis grassland and phragmites australis wetland. The content of SOC was affected by soil environmental conditions and the improvement of soil environment in the restoration process of degraded wetland. It is beneficial to the accumulation of SOC. [Conclusion] The flooding restoration of soda saline-alkali degraded wetlands is conducive to the realization of the goal of "double carbon".