Industrial wastewater sludge contains a certain amount of heavy metals, which will cause environmental pollution. In this paper high Cr, Zn content wastewater sludge from steel plant was used as the main raw material, with Kaolin and other materials as adjustment materials. Through optimization design of raw mix composition and firing system, a kind of function aggregate was got, which had an apparent relative density of about 3.0 g/cm3, a vacuum water absorption between 16%~23%, and a linear attenuation coefficient more than 0.15cm-1. Use XRD and SEM to analyze the existence state of heavy metals in aggregates. The novel method for making function aggregates provides a technical support for resource utilization of steel wastewater sludge, which could be applied in the field of high strength concrete and radiation shielding concrete.