Bamboo is a renewable bioresource with extensive applications, from construction to textiles, and is essential for bioenergy and eco-friendly practices. Despite its potential use in biorefineries, the utilization of abundant species like Dendrocalamus giganteus is hindered by a lack of comprehensive knowledge regarding its chemical composition at various growth stages. In this study, we addressed this gap by quantifying the holocellulose, lignin and extractive contents of D. giganteus from the tropical forests of Bangladesh. We examined the composition across different ages and heights, assessing the solubility of holocellulose, lignin and extractive contents, with a view to enhance the use of D. giganteus in biorefinery industries. We analyzed chemical composition and assessed the solubility using both hot and cold water, as well as conducting 1 % NaOH (caustic soda) solubility tests following the TAPPI (Technical Association of the Pulp and Paper Industry) standards. The holocellulose, lignin, and extractive content increased with the increase age of the bamboo. These components also increased with increasing height, regardless of age. The solubility in water and NaOH, on the other hand, decreased with the increasing age and height positions. The top of 4-year-old bamboo exhibited the highest levels of holocellulose (70.2 %), lignin (29.7 %), and extractive components (6.9 %), but the lowest solubilities in hot water (6.18 %), cold water (3.58 %) and caustic soda (22.48 %). These findings suggest that D. giganteus has potential applications in specific industries, such as pulp and paper, nanocellulose, bioethanol, biochemicals and bio-based composites.