Abstract: The soil available trace elements are very important to plant growing. The paired-site design was used to explore the effect of different grassland use on soil trace elements and evaluate the contents of soil trace elements, which would be helpful to develop scientific strategies for land use in the agro-pasturage ecotone of northern China. In the present study, the contents of soil available trace elements (Cu, Fe, Mn, Zn, B, Mo) were measured in typical grassland, meadow and their counterpart croplands. The results showed that the soil available Cu, Zn contents increased by 8.8% and 16.4% respectively after typical grassland converted into cropland; Soil available Fe, Mn, B and Mo contents decreased by 16.1% to 28.1%. According to soil available trace elements evaluation criteria, the soil available B and Mo were at high level, and Cu at medium level, Zn at extremely low level in both typical grassland and counterpart croplands. The soil available Fe and Mn decreased from high and medium levels to medium and low levels after typical grassland converted into cropland. The meadow reclamation made six soil available trace elements contents decrease by about 10.6%-77.7%, where the available Fe, B, and Mo were at extremely high level, and Mn at medium level, Zn at extremely low level in meadow and counterpart croplands. Soil available Cu decreased from high level to medium level after meadow converted into cropland. The soil trace elements below medium level could not meet the demands of grass vegetation and crop growing. It was suggested that the farmers should reserve high crop residue in the farmland and improve soil quality by returning straw to field and applying trace element fertilizer. Meanwhile it would be an importance to stop reclaiming the typical grassland, to return the crop field into grassland and scientifically use the meadow in agro-pastoral ecotone of northern China. It is suggested that the new evaluation criteria of soil trace element based on soil trace element density should be built.