In the south edge of Hunshandake sand land, the influences of seed source effect ol enclosed grasslana on seed bank around sandy grassland are researched tentatively by contrasting the characteristics of seed bank in different places of sandy grassland out of fence and the grassland which was enclosed for 7 years as contrast. The results show that the seed source effect of enclosed grassland are dramatic on sandy grassland seed bank out of the fence, especially nearly around the fence, and the influences are fade-away gradually out of fence for about 500 meters. In addition, the seed source effect can restore radially the seed bank around sandy grassland.