Urban green space provides a variety of ecosystem services for urban ecological environment health, which is closely related to improving human well-being and promoting sustainable urban development. The carbon sequestration function and potential of urban soil are one of the hot issues in the study of the carbon cycle of the urban ecosystems under the background of global climate change. Urban green space is the only land element with direct carbon sink value in the urban ecosystem, which plays an important role in mitigating global warming and responding to climate change. The quantity and quality of soil carbon pool is an important content to measure the soil health status of urban green space, which is directly related to promoting human health, maintaining biodiversity, and maintaining the sustainable supply of various urban green space ecosystem services, such as landscape recreation. However, the research on the formation and accumulation process and mechanism of soil carbon pool in urban green space is still in its infancy. This study systematically sorted out the definitions and main characteristics of soil in urban green space, summarized the spatial distribution pattern and main influencing factors of soil carbon pool in urban green space, and sorted out the difference between soil carbon flux in urban green space and natural soil and its potential mechanism. This paper focuses on the characteristics and driving factors of soil carbon sequestration in urban green space and discusses the main effects of vegetation, human activities, and time on soil carbon sequestration in urban green space. Finally, the limitations and shortcomings of current research on soil carbon sequestration in urban green space were put forward, and the future research directions and hot spots of soil carbon sequestration in urban green space have been prospected. It provides the scientific basis for improving the soil carbon sequestration potential of green space.