Abstract: The purpose of this research is to study the dental morphology of the neolithic humans in north China and its relationship with modern Chinese origin. The dental specimens used in this research include the neolithic human teeth from Xiawanggang in Henan province and Miaozigou in Inner Mongolia, which were observed by present author. The dental morphological data of some other Asian populations cited from references were also used including the people of Shang dynasty from Anyang and people of south China. In order to study the temporal changes of certain dental traits, some fossil teeth found in China were also used. The results are as follows:
1. The frequencies of most dental morphological traits of the neolithic humans in north China are quite similar to those of other NE Asians and are different from SE Asians. This is especially true in traits of shovel incisor, double-shovel incisor, enamel extension of upper molars, deflecting wrinkle of lower molars and three roots of lower first molar.
2. The temporal changes of certain traits were studied by observing some fossil teeth found in China. Some traits were found to have existed as early as Homo erectus and evolved till modern humans, for example shovel incisor, double-shovel incisor, interruption groove, peg/ reduced/ congenital absence of M3, and deflecting wrinkle. No fossil teeth have enamel extension suggesting this trait occurred only on the teeth of anatomically modern humans. The trait of three roots of lower first molar was found on the mandible of Homo erectus excavated at Zhoukoudian in 1959.
3. Statistical analyses show that the inhabitants of the two sites have closer biological distance with Anyang and other NE Asians than with SE Asians. Cluster analysis indicates there are two population systems in E Asia corresponding to the distribution of Sundadonty and Sinodonty.
4. According to the morphological observation and statistical analyses mentioned above, it seems that Turner's theory of existence of two types of dental morphological traits in east Asians cannot be denied. However, some phenomenons revealed in this research cannot be explained with his idea. So further research is necessary to demonstrate the formation, relationship of the two types of teeth and their roles on modern human origin in this area. The analyses of the distribution and evolution trend for some dental morphological traits indicate: the research of dental morphology will help us clarify the course of the origin and evolution of modern humans in China.

Key words: Teeth; Dental anthropology; Dental morphological traits; Neolithic time; Modern human origins