Impacts on growth of young trees of Pinus Koraiensis of 6 environmental factors of intensity of sunlight, direct sunlight, thickness of soil humus, neighboring trees, upper canopy species, herbs and shrubs were investigated on young tree of Pinus Koraiensis and 4 neighboring trees which are considered the structural unit of the microenvironment. Results indicated that the 6 environmental factors under investigation had effects, to various extents, on growth of the young trees. Based on the findings, suitable growing conditions for regenerated young tree of Pinus Koraiensis under forest were identified and corresponding silvicultural measures were proposed for operational practice.