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Migmatites are widespread in the North Dabie ultrahigh-pressure metamorphic terrane (NDT) of Dabie orogen, East China. Idiomorphic and poikilitic amphibole grains in both leucosome and melanosome contain inclusions of plagioclase, quartz and biotite, suggesting formation of leucosome by fluid-present melting of biotite + plagioclase + quartz-bearing protoliths at P = 5-7 kbar, T = 700-800°C. Precise SIMS zircon U-Pb dating indicates that migmatization of Dabie orogen initiated at ~ 140 Ma and lasted for ~ 10 Ma, coeval with the formation of low-[Mg.sup.#] adakitic intrusions in Dabie orogen. Based on mineralogical, petrographic and geochemical data, leucosomes in NDT can be subdivided into three groups. (1) High [La/Yb.sub.(N)]-Medium Sr/Y group (Group I), whose high [Dy/Yb.sub.(N)] but medium Sr/Y ratios are caused by amphibole and plagioclase residual during partial melting of dioritic to granodioritic gneisses. (2) Low [La/Yb.sub.(N)]-Low Sr/Y group (Group II), whose flat HREE patterns are produced by entrainment of peritectic amphiboles into melts derived from partial melting of dioritic gneiss. (3) High [La/Yb.sub.(N)]-High Sr/Y and [Eu.sup.#] group (Group III), whose extremely high Sr and Eu but low other REE concentrations are caused by accumulation of plagioclase and quartz. Although Group I and III fall in the adakitic fields on [La/Yb.sub.(N)]-[Yb.sub.(N)] and Sr/Y-Y diagrams, they are chemically distinct from contemporary high-pressure adakitic intrusions in Dabie orogen in a series of geochemical indexes, for example, lower [Dy/Yb.sub.(N)] and/or Sr/Y ratios at given [La/Yb.sub.(N)] ratio, lower Sr/CaO ratios, lower Rb concentration but higher K/Rb ratios. Therefore, leucosomes are produced by anatexis of the exhumed ultrahigh-pressure metamorphic rocks at middle crustal level, instead of partial melting of thickened lower crust with garnet-rich and plagioclase-poor residual. The coeval occurrence of migmatites and high-pressure adakitic intrusions in Dabie orogen indicates large-scale partial melting of middle to thickened lower crustal column in the early Cretaceous. The required heat source may be the mantle heat conducting through the lithospheric mantle whose lower parts have been convectively removed. Keywords Dabie orogen * Migmatite * Middle crustal melting * Adakite * Lithosphere thinning, Introduction Partial melting of middle-lower crust is a common phenomenon in many ancient and modern orogenic belts (e.g., Sawyer et al. 2011). Its initiation is a combined response to the [...]