Being widely distributed in the Qinling Mountains,Bashania fargesii is the primary food source for giant pandas (Ailuropoda melanoleuca) during winter and spring.To understand the relationship between panda food habits and nutrients in the bamboo,we collected samples of leaves,branches and stems across seasons and ages in Foping Nature Reserve,Shaanxi Province,China. Each category of samples was collected at the same site,with three replicates,and weighing 200 to 500 gram. Seven trace elements (Zn,Cu,Fe,Mn,Ca,Mg,K) were analyzed by the atomic absorption spectrophometric method. Crude protein was determined following Macro-Kjelhahl procudure,and crude fat was measured with Soxhlet procedure. The results indicated that contents of Mn,Ca,Mg in the leaves and Cu,Zn,Fe in the branches were respectively higher than those in the other parts on bamboo. Compared with those in the branches and stems,contents of crude protein and crude fat in the leaves were significantly higher. In addition,contents of trace elements and nutrients in the bamboos varied across seasons and ages. Leaves are the most nutritious among different parts of bamboo. Food habits exhibited by giant pandas were closely related to nutrition quality of leaves in the bamboo.