Abstract:The relationship between coarse woody debris (CWD) number, existing form, decay class and topographic traits were studied in a large permanent plot (9hm2) of a typical mixed broadleaved-Korean pine forest in Xiaoxing′an Mountains. The CWD density and basal area increased with the topographic position rising; The density, basal area and volume of CWD trended to decrease from north to south slope. There was no clear pattern between the number of CWD and sampled slope. A x2-test showed that topography significantly affected density of the CWD. CWD was liked to occur on ridge, north slope and slope degree of 16-25°.The CWD was mainly composed of uprooted blow-down, breakage at rootstock and breakage at trunk depending on topography. The density, basal area and volume of uprooted blow-down decreased from valley to ridge, but the density of other existing forms showed an opposite pattern; The density of uprooted blow-down decreased with slope degree rising, while that of the standing entire dead trees increased; The density of standing entire dead trees decreased from north to south slope. The falling direction of CWD were not correlated with the aspect and wind direction (p>0.05). The decay classes of CWD were largely normally distributed with a peak on the decay class 2 and 3, suggesting that the input and output of CWD was largely balanced in the mixed broad-leaved Korean pine forest.