The area of primitive forests on the north slope of the Changbai Mountains is one of the beat virgin forest regions reserved in northeast China. In order to study the influence of felling of the primRtive forests on the soil properties and its relation to natural reforestation, the field investigation was conducted from June to August in 1982. The main types of forest vegetation in this region are the pure larch forest, the broad-leaved Korean pine forest, the mixed coniferous forest and the mixed broad-leaved forest. gnd under these vegetations the main soils are mountain brown coniferous forest soils, mountain dark brown forest soil and lessive soil. These sail profiles are characterized by the thicker littear layer, higher content of humus and total nitrogen, which decrease rapddly downwards, pH-value ranging from 5.0-6.0, low degree of base saturation, higher content of hydrolytic acid, insignificant illuviation of iron oxide and aluminum oxide, C/N ratio ranging from 15 to 20 and good physical properties. It can be found that felling of the forest results in great changes of soil properties such as the accederated decomposition of litter, the increase of humus and total nitrogen in topsoil, the decrease of soil acidity, and the improvement of physical and moisture properties of the soil, which are favourable for the reforestation. However, clear felling in a too large area will bring about the flourishing growth of the wild grasses and dense development. of their roots in the topsoil, which is unfavourable for the nahural vend artificial reforestation. Therefore, the ra.tionable felling, i.e. selective felling,rather than the clear felling should be adopted, and the intensity of selective felling should be 40-50%. On the clear felling slash, careful preparation of soil before artifical reforestation is necessary, and proper tending of the young growth is of most important for its rapid growth.