Abstract: China is establishing a mechanism for realizing the value of ecological products from soil and water conservation, incorporating carbon sinks from soil and water conservation into voluntary greenhouse gas emission reduction trading. The development of carbon sink projects and their entry into the carbon trading market hinge on setting baseline scenarios. The trading market requires clear and operational arguments for the additivity of methodologies, ensuring that emission reductions are genuine, accurate, and conservative. However, there is currently limited research in this area. Baseline scenarios typically refer to changes in potential carbon reduction levels in project sites when no soil and water conservation measures are implemented. This study discusses issues related to baselines for soil and water conservation projects from aspects such as definition, characteristics, types, criteria, and determination methods. Based on the basic requirements for baselines outlined in the current CCER methodology call for publication in China, this study analyzes and compares methods for determining baseline activities for soil and water conservation carbon sink projects. When developing soil and water conservation carbon sink projects, a project-level baseline method can be adopted to enhance the consistency, comparability, and overall quality of project baseline calculations.