Abstract: Based on a series of field investigation into psammophytic vegetation in Horqin sandy land and laboratory analysis of soil properties, the relationship between biodiversity and soil fertility characteristics were analyzed. The results showed that plant diversity indices were low in Horqin sandy grassland. There was different effect of soil fertility (0～10 cm layer) on species diversity. Soil organic C, total N, total P, available N had significant or very significant positive correlation with ShannonWiener, Simpson, Margalef diversity indices, but no significant relation with Pielou diversity index. Available P and pH had no significant correlation with diversity indices.