The Qiangtang Basin in Tibet is a largescaled multisuperimposed sedimentary basin. Based on the plentiful data of regional geology and field outcrop observations， detailed researches have been carried out on  the characteristics of different tectonic units of the Mesozoic in the Qiangtang Basin， such as sedimentary filling sequences， stratigraphic development and contacting relationship， properties of structural boundaries， sedimentary systems and facies distribution et al. The coupling relationship between  basin deposition and evolution of adjacent orogenic belts was investigated， and the tectonopalaeogeography in different periods of the Mesozoic were reconstructed in the study area. The researches show that the Mesozoic in the eastern Qiangtang Basin comprised of three sedimentary system sets， nine sedimentary systems and numerous sedimentary(subfacies)facies respectively belonging to marine facies, transitional facies from marine to continental facies and continental facies. There are many tectonic units， for example， North Qiangtang Depression， South Qiangtang Depression， Tanggula Mountains uplifting belt， and some subsalients， faulted sags and uplifts in different stages of the Mesozoic  in the eastern Qiangtang Basin. The Duoma Faulted Sag  is an epicontinental margin basin，located on the passive continental margin， which has a basement of the Precarboniferous tectonic schists， and was superimposed by the Jurassic Early Cretaceous sedimentationLater， during the Early Cretaceous， it transformed into a foreland basin， and since the Late Cretaceous， it has been connected with the SuoxianZuogong Faulted Sag. Totally， during the intracontinental orogenic processes， it experienced multiple compressiondepression evolution of sedimentary filling. The SuoxianZuogong Faulted Sag  is a foreland basin developed during the Late Triassic  based on the trougharcoceanic system. The North Qiangtang Depression was developed based on the Varician KaixinlingZaduo uplift， and followed by the Late Triassic Changdu foreland basin，as well as the Early Jurassic North Qiangtang Faulted Sag volcanicsedimentary basin. During the Middle Jurassic，the North Qiangtang and SuoxianZuogong depressions were combined as a multidepressional basin， and a huge Qiangtang Changdu Depression was formed. The North Qiangtang land block and Changdu land block were uplifted and experienced uplifting and exposure during the Cretaceous.