Abstract: Using whole plastic-film mulching and half plastic-film mulching technology, the inhibition salinity,raise emergence rate and yield of field experiment of sunflower were conducted in Inner Mongolia Hetao irrigation district. The results strawed that the desalting rate of whole plastic-film mulching more than no plastic-film mulching by 44.1% in the top layer soil of moderately severe saline-alkali land with salt content was 3.5-6.0 g/kg,compared with traditional half plastic-film mulching, its desalination rate increased by 14.2 percentage point. At the same time, compared with no and half film mulching ,the sunflower germination rate increased by 45.6 and 17.7 percentage point respectively, and yield increased by 183.3% and 67.0% respectively, which was an effective technology for further improving use efficiency and crop yield rate in the saline-alkali land.