Abstract: [Objective] In order to reveal chemical constituents distribution rule of bamboo fiber cell wall, distribution of some important chemicals within single fiber cell was studied.[Method] Six-year-old moso bamboo (Phyllostachys edulis) was chosen and sampled into ultrathin section as research material. High-resolution confocal Raman microscopy was used to collect Raman spectrum of bamboo fiber in situ. The chemical constituents distribution of moso bamboo fiber cell wall was analyzed through Raman imaging technique.[Result] S unit and G unit of lignin widely distributed in all layers of wood cell wall, but H unit mainly distributed in layers that close to peripheral region. The distribution pattern of hydroxycinnamic acids was similar to that of H unit, i.e. mainly distributed in peripheral region of cell wall. Cellulose had a relatively even distribution in thick layers, and the concentration of cellulose was higher in thick layers than that of thin layers. Lignin concentration decreased from periphery to central part of a fiber cell, with relative higher value at compound middle lamella, lumen edge as well as interface between two layers which formed local accumulation at those regions.[Conclusion] The bamboo fiber cell wall has different chemical composition in radial direction, and cellulose, lignin and hydroxycinnamic acid have different distribution density within different cell wall layers.

Key words: cell wall, Phyllostachys edulis, fiber, Raman spectrum, chemical component