The melting relations, phase compositions, and trace element partitioning behavior during metasediment partial melting were investigated by high pressure and temperature experiments (300 and 900 MPa, 750–950 °C). The here published dataset includes all geochemical analysis of experimental products and starting materials, Raman identification of experimental minerals, and quantification of experimental phase proportions. From this dataset, we provided new insights into the origin of rare-metal enriched granites.