This textbook is intended for studying the disciplines "Wood Science" and "Forest Commodity Science" in technical schools and colleges in training in the areas of "Woodworking Technology," "Logging Technology," "Forestry and Forestry." The textbook discusses the structure of wood at the level of chemical elements, substances, individual cells, at the macroscopic level and tree level; the main physical and mechanical properties of wood, the laws of their change and the factors affecting them are analyzed. The main characteristics of the wood of the main tree species are briefly considered. Wood defects and methods of their measurement are considered in detail.