The function of increasing sinks and reducing emissions of urban green space is an important way to achieve the “carbon neutrality” goal of China in the field of urban human settlements. During the research process from 2008 to 2021, scholars conducted a lot of basic research on carbon sequestration and emission in urban green spaces. In order to explore the usability of existing research results from the perspective of planning and design practice, this paper conducts a cross-classification analysis of the research results of urban green space carbon sequestration and emission from the four levels of a theoretical system, inventory data, impact relationship, and strategy and method combined with different dimensions. The results show that: (1) The research results of the theoretical system have been continuously updated with the integration of interdisciplinary content, but the overall process is slow; (2) Some research results in the inventory data research results in lack standardized accounting boundaries; (3) The current research results at the impact relationship level have an improvement in the multi-dimensional impact factor evidence chain; (4) The research results of strategies and methods have strong pertinence, but their actual effectiveness needs to be verified. In general, this paper effectively reviews and summarizes the existing research results related to carbon sink and carbon emission in urban green space, further points out the future research development direction and content from the perspective of planning and design practice, and clarifies the ideas for the research on low-carbon aspects of urban green space based on the availability of research results.