AbstractThis study explored the chemical properties of heat-treated bamboo. Oriented bamboo fiber mats (OBFMs) of Phyllostachys iridescens bamboo, as units of a bamboo fiber-reinforced composite (BFRC), were heat-treated in saturated steam at 0.40 MPa (150 °C) for 110, 140, or 170 min. After heat treatment, the color of oriented bamboo fiber mats changed noticeably. The chemical properties of the bamboo were examined. The results revealed that the contents of holocellulose and hemicelluloses decreased, while the contents of α-cellulose and water extractives and buffering capacity increased. The pH value decreased compared with control samples. The change in the chemical properties of the OBFMs would have an effect on the properties of the BFRC.