Abstract: Taken the artificial planting Dendrocalamus giganteus forest in Cangyuan County as the research object, based on the preliminary measurement of the biomass and various ecological indicators of 151 D. giganteus aboveground organs, the biomass ratio and water content of the aboveground organs of D. giganteus were analyzed. To construct a power function biomass regression model for the aboveground parts of D. giganteus. The results showed that with the increase of the age grade of D. giganteus, the water content of each organ in the Ⅰ to Ⅲ age grades gradually decreased. The average water content of the above-ground part of individual D. giganteus was 75.01%, 49.35%, and 47.97%, respectively. The water content of the stem of the Ⅰ age grade D. giganteus significantly higher than the Ⅱ and Ⅲ age grades; the average above-ground biomass of individual D. giganteus for Ⅰ to Ⅲ age grades was 16.50, 31.36, 37.64 kg/plant; with the increase of age, the proportion of twig and foliage biomass increases, and the proportion of stem biomass decreases; the diameter at breast height of each age grade of D. giganteus had a good correlation with stem biomass, twig biomass, foliage biomass, and total above ground biomass, and it is extremely significant. The determination coefficients of the aboveground biomass models for each age grades established with the diameter at breast height as the independent variable were all above 0.9. Among them, the determination coefficients of the twig and foliage biomass models for the Ⅱ and Ⅲ age grades are relatively lowly, between 0.7 and 0.8. However, the model significance is less than 0.01.