Abstract:In the process of investigating and handling forestry cases , trees that were cut indiscriminately or illegally, so the DBH（diameter at breast height) of the trees could not be measured. Usually, the volume was calculated by directly es- timating the DBH of the trees based on experience and consulting the one-dimensional Timber Volume Table . How to sci- entifically calculate the DBHand volume by using the ground diameter of trees . In this study, four tree species of Pinus massoniana , Cunninghamia lanceolata, Cupressus funebris and Quercus aculissima commonly seen in Three Gorges Reser- voir Area were selected to analyze the relationship between ground diameter and DBH of each tree species through field random sampling measurement, data analysis , modeling estimation, analysis summary and field verification in Zigui Coun- ty, in Three Gorges Reservoir area, and a one-dimensional volume table for the ground diameter of each tree species was prepared, In addition,the program was compiled in Excel to substitute relevant data, and a calculation table of standing volume of one yuan of ground diameter was made . After selecting tree species , the DBHand volume of the tree species were obtained by inputting the ground diameter value of the tree species , which realized the goal of scientific , rapid and accurate calculation of standing volume in the process of handling the case .