The effects of coarse and fine aggregate of steel slag on the strength, freeze-thaw resistance, permeability resistance and shrinkage resistance of concrete were studied by adjusting the proportion of each component of concrete prepared with steel slag as coarse and fine aggregate. The test results show that steel slag concrete can meet the construction requirements by reasonably determining sand ratio, cementitious material dosage, admixture and other materials, and steel slag as concrete aggregate can significantly improve the microstructure of concrete.