Soil organic carbon (SOC) storage is an important parameter of soil environmental quality, and agriculture soil is easy to be interfered by human activities and also could be adjusted in a short time scales. The ongoing land-use changes in developed area in China have important influence on SOC (soil organic carbon) sequestration. In this research we take Wujiang County as a case, evaluated the influence of land-use changes on the soil carbon sequestration ability in the paddy fields. The land use classification in Wujiang County from 2000 to 2005 were conducted by a new methodology that integrates 8-day composite images (500-m and 250-m spatial resolution) from the moderate resolution imaging spectro-radiometer (MODIS) sensor with Landsat data. The maximum likelihood classification (MLC) method was used to conduct TM/ETM images classification. The vegetation index (NDVI, EVI) and land surface water index (LSWI) mask method was used to conduct MODIS images classification. The land use class map and the density of soil organic carbon (SOC) data from the 2nd State Soil Survey and the nationwide arable soil monitoring system (NASMC) along with county-level soil reconnaissance data were further used to calculate the soil carbon sequestration ability. The result showed that irrigation-based rice cultivation in the study area has induced significant enrichment of SOC storage in paddy soils. But carbon sequestration ability tended to decline over the most recent six years due to decreasing in paddy area and shifting to other land uses. The paddy soils have switched from carbon sink to carbon source since 2001. The total SOC sequestration in 0-15cm soils in 1984, 2000, 2001, 2002, 2003, 2004 and 2005 were 107×10³t,9.2×10³t,-8.0×10³t, -21.2×10³t,-49.2×10³t,-41.6×10³t and -49.4×10³t respectively. The results of this study suggested that land use changes have a great influence on topsoil carbon (C) sequestration, particularly on C stocks and C sequestration potential in paddy fields in developed areas of China.