For creeping stems of lawn grass, one or two buds at the front end of the near growth point can sprout, a plurality of buds at the back end are dormant, only one or two buds at each end of the grass item can sprout, a plurality of buds and internodes become the growth substrate for the sprouting buds at the front end, and the stems and leaves trimmed off can be directly used as the growth substrate of the lawn grass. According to the principle, the invention discloses a method for culturing soil-free lawn in a substrate-free mode. The technical scheme comprises selection of grass seeds, collection of items, paving of an insulating layer, sowing of grass items, water management, nutrient management, lawn trimming, prevention and controlling of diseases, insects and natural grass. The method can save the special lawn-culturing substrate, has the advantages of energy conservation and low carbon, rain wash resistance, quick lawn formation, smooth and dense lawn, strong root system, no soil pollution and short rejuvenation period, and is in accordance with the development trend that the quality requirements of lawn in various urban sightseeing greenbelts and playgrounds are higher and higher.