By reviewing the domestic and international methods of life cycle impact assessment on wood products, two stages of log transportation and sawn timber production were as the study scope in combination with the characteristics of sawn timber products in life cycle assessment.We used global warming, acidification, eutrophication, dust, and solid waste in life cycle assessment, and established a suitable evaluation model from five aspects including energy and material consumption during transportation and inventory analysis, selection of types of environmental impacts, classification of environmental impact factors, calculation of environmental impact load, and weighted and standardized environmental impact potential. We collected the sawn timber related data from a local sawmill and input them in the evaluation model.The global warming and acidification among five environmental evaluation indices had the most environmental impacts, followed by solid waste pollution, smoke, dust, and eutrophication.We put forward some constructive suggestions with regard to sawn timber transportation and production to reduce the potential environmental impacts.