Knowledge of the spatial distribution of the soil carbon stock is essential for assessing the productivity, sustainability, and carbon sequestration capacity of agricultural and forested land. To contribute to the development and improvement of soil carbon models of tropical forest regions, we have collected soil carbon data in Cambodian forests since 2002 to facilitate several research projects conducted by the Forestry and Forest Products Research Institute. Our dataset contains meta-data for 66 sites (site data) and data for 309 soil horizons (soil profile data). The data for 36 sites are newly described herein, while the data for the other 30 sites are derived from the synthesis of published documents.