Based on the samples of the coarse woody debris (CWD) of major six species of deciduous and coniferous trees in paleoperiglacical landform forest of the Mt.Laotudingzi, eastern Liaoning mountainous region, by the methods of natural wind dry, indoor soak and Xray fluorescence, this paper had a systematic research on waterabsorption rate, waterabsorption ability and the nutrient element content of CWD. The results were as follows: (1) The water absorption equals a precipitation of 2.533 mm in the 8 hours constant soaking process, and 60% of it was made in the beginning 15 mins. In the comparison of each single sample, 900 m altitude trees, deciduous trees, high decay class, logs and roots showed better ability of waterabsorption.(2) Element slowly releasing and enrichment function of CWD: The percentage of Carbon is 78.96% in sapwoods and that in heartwood is 96.05%. It was also found that the element N, Ca, Si, K, Mg, P contents in sapwoods were 4.93, 5.88, 10.79, 2.72, 1.25 and 2.38 times as that in heartwoods correspondingly. The contents of nutrient elements had a minor difference in the sapwoods of each sample, among which, the CWD of coniferous trees and high decay class reveal higher carbon content while the CWD of deciduous trees and low decay class have a higher nitrogen content and above all, snags have a high content of both two elements. The research indicated that: CWD had an important function of waterholding, nutrient element slowly releasing and enrichment in the paleoperiglacical landforms forest ecosystems of eastern Liaoning mountainous region; the sapwoods play a more important role than heartwoods in the aspect of nutrient slowly releasing and enrichment. Since the land has a low soil coverage rate and the soil layer on land is thin and barren, the CWD is an irreplaceable and crucial ecological component of paleoperiglacical landform forests.