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The failure of natural dams formed by landslide and glacier in mountain area have triggered the most destructive flood events on Earth and other planets. It has been evoked that outburst flood is a very effective agent to modify landscape, such as curving bedrock gorge, and transport surface mass, which may impose long-lasting imprint on fluvial geomorphology. Recently, it is widely debated that the focused incision given risen by high-magnitude outburst floods has contributed to the rapid uplift of Eastern Himalayan Syntaxis. Previous studies have identified three dammed lakes in the valley of Yurlung Tsangpo, namely, Gaga Lake, Dazhuka--Yueju Lake and Jiedexiu Lake. However, the causal relationship between these dammed lake and outburst floods is unclear due to the lack of a robust chronology. Especially, the sediment formed by cataclysmic process may experience short bleaching history which result in unfavorable luminescence characteristic to obtain reliable ages. This problem hinders the estimation of the expected repetition time for the events of such magnitude which can be key input for quantitative geomorphic evolution model. Here, we presented 15 optically stimulated luminescence (OSL) ages in the middle reach of the Yarlung Tsangpo River, primary from lacustrine, colluvial, and eolian sediments associated with river blocking, to reconstructed the evolution of the Zhaba dammed lake. A combination of the single-aliquot regenerative-dose (SAR) protocol and the standard growth curve (SGC) method was applied to determine the equivalent dose of 38-63μm quartz grains. Utilizing luminescence characteristics analysis of quartz OSL ages, the reliability of quartz OSL ages was tested. The findings of the study suggested that the Zhaba dammed lake formed before 44.68± 3.64 ka, but the quartz OSL signal show saturation trend which is a common phenomenon in OSL dating. Younger sediments formed between 16.89±1.40 ka and 15.10±1.20 ka, which illustrates that the Zhaba dammed lake at least continue until 20 ka. Furthermore, continuous clay varve also implies the lake maintain stable for a long period of time. Hence, during the Holocene altithermal period, the Zhaba dammed lake likely to have collapsed and caused a catastrophic outburst flood events in the Yarlung Tsangpo river. [ABSTRACT FROM AUTHOR]