Studies of the East Asian Neolithic have been conducted for more than a century and many attempts have been made to interpret the functions of prehistoric pottery, particularly the earliest ceramics. The unsophisticated pottery discovered in the Weijiawopu site opens a window for the study of early ceramic function. We conducted plant residue analyses of ceramics from the Weijiawopu Neolithic site; the largest Hongshan Culture settlement in Inner Mongolia, China. The site is thought to belong to the early to middle period of the Hongshan Culture, approximately 6500-5500 cal BP. Based on evidence from starch grains, we identified four main plant resources: 1) cereal grains; 2) Dioscorea plant tubers; 3) beans; and 4) nuts. None of the individual starch grains exhibit surface damage, indicating they did not undergo extensive processing such as grinding or cooking. Hence, we conclude that the pottery samples analyzed derive from food storage containers, indicating one major function of early pottery at the site. Furthermore, wild plants are thought to have been an essential part of the Weijiawopu people's subsistence base, suggesting a mixed economic pattern based upon both domestication activities and hunting-gathering-foraging lifeways.