The invention provides full-nutrient interference liquid for four-season waterless trees in arid regions and a preparation method of the full-nutrient interference liquid. The full-nutrient interference liquid is formed by culturing photosynthetic bacteria, lactic acid bacteria, actinomycetes, filamentous bacteria and saccharomycetes and fermenting the bacteria with other strains, minerals and special additives, wherein the contents of the photosynthetic bacteria, the lactic acid bacteria, the actinomycetes, the filamentous bacteria, the saccharomycetes, the strains, the minerals and the special additives are 0.3-0.5%, 0.4-0.6%, 0.6--0.8%, 0.2-0.4%, 0.9-1.1%, 0.4-0.6%, 50-55% and 47.2-50% by weight respectively. Seedlings treated by the full-nutrient interference liquid are planted in northern regions with the annual rainfall of 100-400 mm without watering, watering is not needed in a three-year breeding period, and the trees can be planted in four seasons. The afforestation efficiencyis greatly improved, the afforestation cost is effectively reduced, water resources are greatly saved, and the afforestation area is enlarged.