This study investigates the Phyllostachys aurea bamboo mesostructure through optical microscopy and digital image processing. Specimens were produced using a bamboo full-culm with cross-sections sliced from 1, 4, and 6 meters distant from the ground. Digital images captured through light microscopy with the magnification of 200x were digitally processed for the segmentation of sclerenchyma, vessels, parenchyma, and epidermis phases, allowing for the extraction of the material’s anatomical features. Binary images obtained from each phase were produced and, then, measured, showing portions of the constituent phases of P. aurea cross-sections at the bottom, middle, and top parts of the culm, respectively.