Abstract: Abstract: Ramie is a perennial crop and is normally harvested three times a year. The mechanical and physical properties of ramie differ from each period due to the different growth climate and environment. The first period of ramie was abundant from late May to early June, the second period was abundant in early August, and the third period of ramie was abundant in late October. It was discovered that the separation of ramie stalk has a lot to do with the time of harvesting, storage, stripping, and moisture content. The ramie stems of the second harvest were struck and used as the objects of study. Impact tests of the ramie stems of the second harvest were carried out to discover the distribution law of fracture energy and to design the mechanical peeling parameters of ramie harvest and store. According to the standard of GB/T 1843-2008 with a TF-2056B Izod impact testing machine, the ramie stems varying in moisture percentage were struck in different parts. Tests of ramie stalk impact fracture energy under different conditions of moisture content were carried out to investigate the biggest impact fracture energy, and the result can provide a theoretical basis and main technical parameters for the determination of time for harvesting, storage, stripping, and mechanism design for low energy consumption with high efficiency separation.Method of control variable was used for the impact tests of 3 kinds of ramie stalk samples. Sample 1 was made to be a standard sample without gap type sheet by cutting the lower end and the middle tip of the ramie stalk to a length of (80±1) mm, width of (6±0.1) mm, and thickness of (3±0.1) mm according to the GB/T 1843-2008. Sample 2 was composed of the lower end, the middle, and the tip of the ramie stalk, which were cut to be cylindrical specimens of whole stalk with the xylem and phloem with the length of (80±1) mm. Sample 3 was composed of the lower end, the middle, and the tip of the ramie stalk which were cut to be cylindrical specimens of whole stalk without phloem with the length of (80±1) mm. The experiment involve two processes: firstly, the impact test for samples 1, 2 and 3 were carried out to investigate the distribution law of the impact fracture energy of the whole stalk of ramie with the moisture content of 84.04%. Secondly, the part with biggest impact fracture energy as a standard according to the distribution law was selected. Then, this was followed by investigating the change trend of ramie stalk impact toughness which was changed with the moisture content, the impact test of the same part from samples 1, 2 and 3 with the moisture content of 84.04%, 82.37%, 81.71% and 73.18%.The results showed that when the moisture is 84.04%, the impact fracture energies of ramie from top to bottom and the xylem of ramie stalk part were in the range of 0.1860-0.7460 J and 0.0550-0.29100 J respectively. Meanwhile, the average impact fracture energy of the standard samples from the top to bottom was 0.0571, 0.0520 and 0.0528 J, and that of the pectin adhesive layer was 0.3072, 0.2165 and 0.1662 J. In the moisture percentage of 84.04%, 82.37%, 81.71% and 73.18%, the average impact fracture energy of the bottom was 0.0571, 0.0549, 0.0543 and 0.0528 J; the xylem of ramie stalk part was 0.5067, 0.4404 , 0.4227 and 0.4031 J; and the woody bottom parts was 0.0240, 0.1824, 0.1676 and 0.1658 J. The results stated that with a decrease in moisture content, the impact of the lower portion of the fracture toughness of Ramie stalk gradually becomes smaller. However, with the moisture content decreased, stalks gradually dry, phloem and xylem become withered and adhesions, and ramie stalk separation showed poor results. Therefore, the ramie stalk should have been harvested and stripped in time.