The Haminmangha site is located in Kezuozhongqi, Inner Mongolia, China, and belongs to the middle Neolithic culture. Its discovery contributes to the revelation of motivation of Haminmangha culture’s development, and the same goes for the restoration of vicissitude process of prehistorical culture in Horqin sandy land. For this reason, trying to reconstruct the living subsistence economy of these ancient people and make the results helpful to summarize the cultural status is an important part of understanding this site. At present, we already have the related results by using methods such as Archaeobotany, Zooarchaeology and dental microwear analyses. Through them we can be preliminarily showed by the subsistence economy status of ancient people in Haminmangha site. However, limited to the methods themselves, it still can’t be told that how the millet farming, hunting, fishing and gathering share the proportion of subsistence economy in Haminmangha site. Beyond that, we also need to figure out whether the livestock raising exist at that time. In order to explore the explanation of those questions, carbon and nitrogen stable isotopic analysis were performed on 87 human bones and 18 animal bones from Haminmangha site. The results show that: human of this site got a wide range of δ¹³C with the value as -14.0‰~-9.0‰ and the average as -11.0‰±1.0‰; the range of δ¹⁵N value is as 8.6‰~11.4‰, the average is as 9.5‰±0.5‰. The results show that diet of wild terrestrial animals was almost based on C₃ plants, while Canidae were fed a fodder with millet and leftovers from human. Human ate a similar, mixed diet with and C₄ plants (millet) and meat come from Canidae. Isotope data shows a significant negative correlation between δ¹³C and δ ¹⁵N of human, suggests an important status of wild terrestrial meat in the diet. Females consumed relatively more millet and less meat, differing significantly from males in terms of food composition. For living subsistence, hunting and farming were of the most important, with fishing and gathering as important supplements. Besides, there was a livestock raising behavior in this site, which took the Canidae as the object.