Abstract: In this paper, the sunlight-dual-conversion film mulching relies on adding the photoluminescent materials that were so called sunlight-dual-conversion agent (SDCA) to regulate light quality and intensity penetrating through it. The ultraviolet or green component of sunlight can be converted into blue light or red light at the same when the sunlight passed through the plastic film containing SDCA. The results of three years tests in agriculture showed that the sunlight-dual-conversion films have the functions of increasing temperature and promoting tobacco growth. The sunlight-dual-conversion films has remarkable temperature-increasing capability and its temperature increment ranges within 0.9~2.1℃ in greenhouses. The greenhouses with the sunlight-dual-conversion film as its coverage could increase the chlorophyll content and Net photosynthetic rate and the dry weights of the roots, stems and leaves of tobacco seedlings and the contents of starch, soluble sugar and crude fiber in the roots, stems and leaves of the seedlings. It helps tobacco seedlings to improve adversity-resistance.