The Early Paleozoic—Caledonian tectonic event of Altun—Qilian—Kunlun orogen has been always the research hotspot at home and abroad. Plenty of research results were published in these years. This paper mainly investigated the geochemical characteristics of the important components of the tectonic melange zones, such as the ophiolites, magmatic rocks and HP—UHP metamorphic rocks, especially the results of the isotopic geochronology. The geochemical characteristics show that the ophiolites have two types, MORB and OIB, whether the ophiolites developed in the mature ocean, small ocean basin, or fore arc/back arc basin remains controversial today. According to plenty of isotopic geochronological data, the Proto Tethys in Altun—Qilian—Kunlun area developed into mature-ocean stage in Cambrian, started to subduct in Middle—Late Ordovician, and became to the post collision and extension environment in Late Silurian Epoch—Early Devonian Epoch. Furthermore, the North Altun and the North Qilian, the South Altun and the North Qaidam, the West Kunlun and the East Kunlun were the same tectonic belt in Early Paleozoic, respectively, which were fractured by the Cenozoic Altun Tagh strike- slip falut.