Paddy field is one of the largest arable lands in China. Soil organic carbon (SOC) in paddy field is an important agricultural carbon pool, which is considered to play a crucial role in slowing down the rise of atmospheric carbon dioxide (CO₂) concentration and global warming. Therefore, it is necessary to clarify the characteristics and influencing factors of SOC sinks in paddy fields of China, which is beneficial to formulate reasonable agricultural management measures and enhance the soil carbon sequestration potential of paddy fields scientifically. According the previous researches, there are regional differences in the spatial distribution of SOC contents in paddy fields of China. Generally, SOC contents in paddy fields of south and southwest China are higher than that of north and northwest China, and that of the middle reaches are higher than the lower reaches of the Yangtze River. Moreover, SOC contens in paddy fields is increase with the increase of altitude but decrease with the increase of soil depth. For the composition of organic carbon in paddy fields, the proportion of inert carbon (more than 60%) is much higher than the activated carbon (less than 5.3%), thus the inert carbon is vital for carbon fixation. For the influencing factors, human management measures are mainly responsible for the change of carbon sink in paddy fields, and which are also closely related to natural factors. In order to maximize the function of carbon sink in paddy fields, the mechanisms of SOC stability should be strengthened in the future research, and the agricultural management should be developed according to local conditions, so as to provide scientific basis for achieving the goal of carbon peak and carbon neutrality in China.