There is a giant Central Orogenic Belt (COB) in central China, which extends over 4000 km from West Kunlun on the west, through Altun, Qinlian, Qinling, and Dabie, to Sulu on the east. This paper is to report that micro-grains of diamond were discovered as inclusions in zircons from both eclogite and its gneissic country rocks in North Qinling, middle part of COB. SHRIMP U-Pb dating of zircons from granitic gneiss yielded 507 ?8 Ma for metamorphic rims and 1200~1800 Ma for relic magmatic or old cores, suggesting an Early Paleo-zoic ultrahigh pressure metamorphic event. The discovery indicated that supracrusts in North Qinling have been subducted to depths >120 km, which together with an Early Paleozoic suture reported in the region suggests an ealy collision between North China Plate and Yangtze Plate. Previous study indicates that an over 350 km long coesite-bearing UHP terrane of Early Paleozoic age has been discovered in Altun and Qilian, west part of COB, and an over 1000 km long diamond- and coesite-bearing UHP terrane of both Early Paleozoic and Trias-sic ages was developed in Dabie-Sulu, east part of the COB. This new microdiamond occurrence forms a bridge between two ultra-high pressure metamorphic terranes recognized in the western and eastern parts of China, thereby confirming the existence of the World's largest ultra-high pressure metamorphic belt extending >4000 km. The existence of such a belt, where the ultra-high pressure metamorphic events are dated from west to east as 500 Ma (South Altun) , 495 Ma (North Qaidam) , 507 Ma (North Qinling, this study) , or, 420~400 Ma (Qinling and northern Dabie) and 240-200 Ma (southern Dabie and Sulu) suggests that in general at least two events of large-scale plate subduction and collision, i. e. , Early Paleozoic and Mesozoic, between the North and South China plates have been recorded. Similar evidence of repeated subduction to and exhumation from great depths occurs in Western Europe in the Variscan and Alpine orogenies of Mesozoic and Tertiary ages. These examples of very deep subduction during recurrent continental collision along belts extending thousands of km suggest that UHPM is probably a common rather than an exceptional occurrence during continental colli-sion, with significant implications for processes of plate tectonic reorganization and mantle mixing over time.