The invention relates to a Panax ginseng planting technique and in particular relates to a method for improving soil for nonforest land planting of Panax ginseng by green fallowing. Green fallowing is one of soil fallow methods and involves one-year or two-year fallow. During the first year, highland barley or green manure crop is planted and highland barley is returned to the farmland and the farmland is ploughed; and during the second year, the farmland is ploughed, organic fertilizers are applied and the soil is sterilized. The green fallowing is a fallow method characterized in that during the fallow process, green manure crops or plants with soil improving effect are planted and applied to the soil before seed setting. The method improves the soil during the fallow period by scientific selection of highland barley varieties, increases the content of soil organic matters, forms a forest soil-like environment, achieves the effect of green soil improvement, provides nutrients necessary for Panax ginseng growth, provides soil guarantee for nonforest land planting of Panax ginseng, and is favorable to nonforest land production of Panax ginseng.