The chemical composition and anatomical structure on mature Schizostachyum brachycladum Kurz investigated. Harvested four-year-old bamboo culms segregated into the bottom, middle and top portions. The samples then undergo the Scanning Electron Microscopy (SEM) to determine their structure such as vascular bundle, parenchyma, and sclerenchyma, and Fourier Transform Infrared Spectroscopy (FTIR) to detect and quantify the changes of chemical composition of bamboo under the different variables which were extractive and the free extractive. The anatomical structures and the chemical compositions of the bamboo culms such as the extractive, holocellulose, alpha cellulose, hemicellulose, and lignin contents were analyzed. Standards by the Technical Association of the Pulp and Paper Industry (TAPPI) followed. Results show the chemical composition especially the extractive, and alpha cellulose were higher at the bottom portion around 5% and 54% respectively, while top portions shows higher in the value of the holocellulose and hemicellulose at 90% and 51%, respectively. The lignin content was higher in the middle portions at 20%. The SEM viewed cell wall structure of vascular bundle, parenchyma, sclerenchyma, and vessel. The different part of mature S. brachycladum Kurz which are top, middle and bottom at the 50X magnification viewed. The FTIR spectroscopy which are applied for the determination, quantify, and detected of chemical composition, lignin distribution, changes in wood properties during wood composites manufacture, wood density and discrimination of wood and non-wood from various species. The O-H stretching absorption bands (around 3600-3200 cm-1) and C-H absorption bands (around 2927 cm-1) have contributions from all these chemical components.