The pyrite smelting slag as industry waste residue was always fully studied in the present research. Due to the complexity of the property of the waste residue,which the environmental hazards of has been discussed in the experiment. Firstly, the complex composition of the waste residue and the primary contamination of heavy metals which included the Copper, Cadmium, Zinc, Nickel, Lead, Chromium and Arsenic usually were determined by XRF scanning. the result of XRF scanning also showed the value for reuse of the waste residue.Secondly,the test investigated the leaching toxicity of the waste residue,the results indicated that the heavy metal of the residue was in low concentration ,in the other words,the slag lixivium was in the range of the required standard, the pyrite smelting slag does not belong to hazardous wastes. The Copper, Zinc and Nickel had not exceeded the standard limit,however, the waste residue could contaminate the surrounding environment if it didn’t been disposed with proper methods.based on the further study, the residue belongs to Class Ⅱ General Industrial Solid Waste and the main phase present in pyrite smelting slag were silicon oxide. Thirdly, through XRD spectra analysis,it can be indicated that waste oxides and sulfate facies were the major phases of heavy metals. So,in order to prevent these potential risks,some effective protection measures should be taken.