Diet bamboo Fargesia nitida of giant pandas at the Jiuzhaigou Nature Reserve was sampled randomly to measure its morphology and biomass in April and July 2009 and April 2011.Biomass models are developed biostatistically to characterize relationships between biomass and morphological indices.The results show that,1) height of bamboo contributes most to biomass,the number of leaves the second,and then the number of nodes and basal diameter the least.A model with height,basal diameter,the number of leaves and nodes fit better than the model with only height and basal diameter.2) above ground biomass of bamboo is the best predict of underground biomass.