Photosynthesis and water utilization efficiency of wild bitter bamboo(Pleioblastus amarus) were measured using portable photosynthetic analyzer LI-6400TX in order to provide a scientific basis for the management of Bitter Bamboo.Results showed that the curves for diurnal changes in net photosynthetic rate and stomatic conductance of Bitter Bamboo exhibited two peaks and the obvious phenomena of midday depression.Stomatic conductance had a significant linear relation with net photosynthetic rate.Stomatic conductance was found to be a key limiting factor for the photosynthesis of Bitter Bamboo and therefore,the midday depression was mainly regulated by the stomatic factor.Water utilization efficiency of Bitter Bamboo was relatively low,indicating that it is poor in water-saving and drought resistance.Light compensation point and light saturation point of Bitter Bamboo leaves were 8.10 and 1 198.66 μmol/(m²·s),respectively,indicating that Bitter Bamboo is a shade-tolerant species and can adapt to a wider lighting condition.