Lagkor Tso, a saline lake located south of Gertse in western Tibet exhibits spectacular flights of paleoshorelines. Optically stimulated luminescence (OSL) dating on quartz using the single-aliquot regenerative-dose (SAR) protocol from five paleoshoreline deposits shows that the lake level was 130 m higher than the present lake surface 5.2 ka ago. The lake level dropped rapidly by ∼25 m between 5.2 ka and 3.7 ka ago. Lake shrinkage further accelerated between 3.7 ka and 3.2 ka ago, when the lake level was just ∼74 m above the present lake surface. Luminescence characteristics and problematic samples are discussed.