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To screen soil nutrients and light conditions that effectively promote the growth of Picea koraiensis saplings and to provide a scientific basis for establishing growth promotion techniques for P. koraiensis saplings, a split-zone design experiment was conducted with P. koraiensis saplings plantations of 8-10 years old in Jiamusi City, Heilongjiang Province, using three light conditions (full light, 0. 5 depression, 0. 7 depression) with nitrogen addition (100 g / plant-yr) and control plots to analyze the effects of light and nitrogen addition on growth and leaf morphological function of P. koraiensis saplings. The results showed that: The annual growth of tree height was the highest under full light conditions, and the annual growth of ground diameter was the highest under full light fertilization conditions, followed by 0. 5 degree of depression; the effect of N addition on the annual growth of tree height and ground diameter was small. Between different light conditions, with the increase of canopy density, the specific leaf area and chlorophyll content increased, leaf dry matter content and chlorophyll a/b decreased, and leaf nutrient content did not change significantly; the effect of N addition on leaf morphology, chlorophyll content and leaf nutrient content was not significant. The effect of light on the growth, leaf morphology and photosynthetic capacity of P. koraiensis saplings was more significant than that of N addition, and saplings under full light and N addition had larger annual growth of tree height and ground diameter, and the lowest annual growth ratio of high diameter. Nitrogen addition can promote the photosynthetic efficiency of saplings. The full light condition or nearly full light condition should be selected for the forestation of P. koraiensis, and the photosynthetic capacity of saplings can be improved by nitrogen addition after forestation to promote growth. [ABSTRACT FROM AUTHOR]