Abstract: The food habits of sambar deer, an animal accompanied with the giant panda, were analyzed for six months by means of microscopic image analysis of feces in Wuyi Shed, Wolong National Nature Reserve. The results showed that sambar deer had the habit of eating bamboo leaves, and the amount of bamboo leaves they consumed changed with the season. When the food was abundant, they ofen feed on woody leaves and dicotyledonous herbs, and the proportion of bamboo leaves was relatively low. With the advent of winter, the food resources were reduced, the sambar deer would gradually increase their dependence on bamboo leaves, especially in February with thick snow. The relative density of bamboo leaves residues in feces was as high as 91.82%. At least in winter, the feeding activities of sambar deer establisded the food competition relationship with giant pandas. Effective management and control of sambar deer density is one of the measures to be considered in the habitat protection of giant pandas.