This study presents a high-resolution (1 km) physically-based solum thickness dataset for the Qinghai–Tibet Plateau. Grounded in a mechanistic mass-balance model that couples climate weathering with multi-process erosion, the data resolve geomorphological patterns and offer superior accuracy over conventional statistical products. This dataset provides essential model parameter for hydrological, ecological, and cryosphere models, facilitating more reliable assessments under a changing climate.