Abstract: Yuanmou Man site is a bout 5 km southeast of Yuanmou county , north pa rt o f Yunnan Province. Two incisor teeth of Homo erectus w ere found on surface of hill top at piedmont of Dongshan ( East mounatain) in the Yuanmou basin 1965. The fossil teeth with mammalian fossils buried in a pluvial fa n deposits at piedmont in the Early Pleistocene. Horse and rhinoceros fossil teeth w ere collected from the site and among their 14 tooth samples w ere selected for electron spin resonance ( ESR) dating. These fossil teeth contain high level uranium. U-content in a dentine sample reaches to 248 μg· g- 1 , and U-content in a sediment sample reaches to 26μg· g- 1 . Calculating ag es of two dating samples, ages o f early uranium uptake ( EU) model are 0. 90_ 0. 97 Ma and linear uranium uptake ( LU) model are 1. 5_ 1. 6 Ma; three U-content high level samples ag es of EU mode are 0. 67_ 0. 81 Ma and LU model are 1. 12_ 1. 15 Ma. Considering that these fossil teeth buried a long time (> 1 Ma) , and the pluvial deposits contain abundant underground water which carrying uranium and post deposit U was continuously accumulated in these fossil tooth , therefore, LU model is adopted to be better and reasonable. i. e. these fossil buried ages o f Yuanmou Man site are more than 1. 1 Ma and less than 1. 6 M a. The results o f da ting ag es show that Yuanmou Man can compare with Turkana Man ( 1. 6 Ma ) o f Kenya, Africa and also belongs to the Early Homo erectus. The dating results correspond to palaeomagnetic measured results for the deposits a t Yuanmou site. The results a re 1. 63 _ 1. 70 M a, in period of Gilsa event, Ma tuyama Reversed Epoch. Age results mentioned above also show that the Yuanmou Man site is one of Early Homo erectus sites of Early Pleistocene in the world.

Key words: Early Homo erectus age, ESR dating , Yuanmou Man site