Abstract: Late Cenozoic sediments in the Kokyar section in the front of the West Kunlun record the uplift process of the Qinghai-Tibet Plateau.Paleomagnetic study shows that the molasse in the front of the West Kunlun formed in the late Miocene to early-mid Pliocene,reflecting that a rapid uplift process took place in the West Kunlun-Qinghai-Tibet Plateau in the late Miocene.Analysis of the sporopollen record and regional geological data indicates that the thick-bedded conglomerate in the upper part of the Kokyar section should be early-middle Pliocene in age,while the deposition of the entire molasse should begin still earlier,i.e.in the late Miocene.The depositional record and climatic change suggest that a prominent tectonic uplift event occurred on the Qinghai-Tibet Plateau in the late Miocene.