Abstract: A great number of Pleistocene fossil orangutan teeth have been discovered in south China in recent decades. These materials will play an important role in understanding the large ??hominoid evolution and environmental change in eastern Asia. In present paper, total 192 postcanine teeth of Pleistocene fossil orangutan from at least 17 localities of south China are measured for tooth crown size (MD×LB) and compared with the data of Holocene subfossil and extant orangutan from Indonesia by Hoosier’s ( 1948) . The results indicate that there are statistically significant differences in postcanine tooth crown sizes, mainly in premolars and first two molars between three groups. The Pleistocene orangutan teeth from south China are significantly bigger than that of the extant orangutan, and also somehow bigger than that of those Holocene subfossil orangutan from Indonesia. The results indicate it is acceptable that the Pleistocene fossil orangutan in south China is assigned to one subspecies, Pongo pygmaeus weidenreich (Hooijer, 1948) .

Key words: Fossil orangutan; Dental morphmetric; Tooth crown size; South China; Pongo pygmaeus weidenreich