Abstract: The metamorphic core complex is an important rheologic pattern of continental extension．The metamorphic core complexes and extensional tectonics have been being a hot-point in the international continental dynamics study in recent 20 years．Based on a large number of recent publications and data，the latest research progress on the metamorphic core complexes is reviewed briefly；the basic features of geometry，kinematics，geochronology ale described roughly；the main characteristics of major detachment faults bordering metamorphic core complexes are analyzed in detail；the tectonic set-tings under which the metamorphic core complexes were formed and the metallogenesis related to metamorphic core complexes are introduced；and the distinguishing indicators of the metamorphic core complexes ale synthesized. Some debated problems are also discussed in this paper including (1) If an important crustal section necessarily be omitted for all the metamorphic core complexes or not? (2) During the development of metamorphic core complexes，whether the magmatism and deformation is caused by extensional tectonics，or the extensional tectonics is induced by magmatism? (3) the genetic mechanism of low-angle normal faults．By contrast with many metamorphic core complexes over the world，we suggest that a major omission of crustal section is not the most important and necessary condition constraining the metamorphic Core complexes．Further studies on the metamorphic core complexes and extensional tectonics will largely promote our understanding of continental rheology and dynamics