Abstract: The Gangdese belt is the giant Cu belt in the Tibet Plateau where three periodic porphyry Cu mineralization were generated during the subduction in the Mid-Jurassic,collision in the Eocene,and post-collision in the Miocene,respectively.The Miocene is the most intensive porphyry Cu mineralization period when lots of large and super-large porphyry Cu deposits including the largest Qulong Cu deposit in China with the Cu resource over 10Mt were generated.Based on many detail field surveys and comprehensive studies,we concluded that the host intrusive is not the classical single porphyry but the composite small porphyry emplaced in multi-stages during the similar time.The mineralization and the subsequent modification followed the every emplacement of composite small porphyry.The large alteration and mineralization do not center on the single porphyry and the ore-forming material and fluid are not directly from the porphyry but from the secondary magma chamber in about 10km underground.The composite small porphyry is generated during the magma evolution in the same magma chamber.The multi-stages magma emplacement supply ore-forming material,fluid and thermo-motive and are the most important prospecting indicators of large and super large porphyry Cu deposits.We presented a new metallogenic model that more emplacement times of composite small porphyry and more complexity of lithology and mineralized elements in the same geological setting are more suitable for the formation of large and super large deposits.This new model not only extends and supplements the classical porphyry Cu model but also has important guiding and reference meanings in the work plan for exploration and evaluation and in the prospecting breakthrough in the Gangdese Cu belt.