Bamboo charcoals were prepared by carbonizing Mosochiku (Phyllostachys pubescens Mazel ex Houzeau de Lehaie), Hachiku (Phyllostachys nigra Munro var. Henonis Muroi), Medake (Pleioblastus simonii Nakai), Madake (Phyllostachys bambusoides Siebold et Zuccarini) and Kurochiku (Phyllostachys nigra Munro). Comparing the pore-size distributions of the bamboo charcoals obtained, it was found that bamboo charcoals prepared from Mosochiku possessed a large number of mesopores in the range of 10-20nm in radius. The pore structural properties of bamboo charcoals prepared from different parts of Mosochiku were investigated. Bamboo charcoals prepared from inner parts of a bamboo trunk possessed larger pore volumes than those from outer parts. Pore-sizes of bamboo charcoals prepared from a thin trunk were small. Bamboo charcoals prepared from a thin trunk and roots of a branch possessed large pore volumes in the range of 3.7-10nm in pore radius. Bamboo charcoals prepared from inner parts of a thick trunk were the most suitable for the humidity-control materials.