This database presents a comprehensive collection of soil and climatic variables associated with the ecological functioning of pure and mixed forest ecosystems across China. It is designed to support comparative analyses and modeling studies on forest management, biodiversity, and ecosystem services.The dataset encompasses key soil properties—including soil organic carbon, pH, bulk density, and moisture content—alongside critical climate variables such as mean annual temperature, precipitation, and seasonal climatic extremes. Data were compiled from field surveys, national forest inventories, and meteorological monitoring networks, standardized and georeferenced for consistent spatial analysis. Focusing on the contrast between pure-species plantations and multi-species mixed forests, this resource enables researchers to examine how forest composition influences soil health, nutrient cycling, water regulation, and carbon sequestration under varying climatic conditions. The database is particularly valuable for studies on sustainable forestry, climate change resilience, and ecological restoration. All data have undergone quality control and harmonization, with metadata provided for traceability. The dataset is available in structured tabular format and can be accessed for non-commercial research purposes to advance understanding of forest ecosystem responses to environmental and management drivers.