Anatexis of lower crustal rocks is not only closely associated with the formation of granulite and granite, but also can affect the geodynamic evolution processes in some tectonic environments. Based on internally consistent thermodynamic database, programs like THERMOCALC/Perple_X and appropriate activitycomposition models for solid solutions, metamorphic phase equilibria modeling has gradually become a common research method in metamorphic petrology, and is widely used for the deduction of mineral paragenesis, estimation of the metamorphic PT conditions of natural rocks, etc. Moreover, if proper activitycomposition models for melt exist, metamorphic phase equilibria modeling can be used to estimate melting temperatures, pressures and the proportion of melt, to confirm involved melting reactions, and to calculate compositions of melts, peritectic minerals and residual minerals. For melts derived from rocks of different compositions, including granitic rocks, metapelites, metabasic rocks and peridotites under different pressures, previous researches have successively raised associated activitycomposition models, which have been confirmed to be valid according to related experimental data. Along with the successive updates and improvement of activitycomposition models for melts in recent years, metamorphic phase equilibria modeling is anticipated to become a common method to study natural anatectic rocks, and provide new research avenues to discuss granulite and granite formation, and associated geodynamic evolutions.