Abstract: The lignocellulosic materials exist in large quantities on the earth and come from a wide range of sources. The treatment of lignocellulosic waste allows for the recycling of waste, and avoids environmental problems. Due to the thick cell walls of lignocellulosic materials and the cell walls contains crystalline structures, pretreatment is required before transmission electron microscopic observation. The sample pretreatment methods of lignocellulosic materials were described in detail, including sampling, fixation, washing, dehydration, resin embedding and penetration, slicing and dyeing, so as to provide a reference for the preparation of the kind of materials.