Abstract: SO₂ in waste gases has been reducted to elemental sulfur as a recovery product (under suitable reaction condition and with carbon as reductant). The product sulfur is a light yellow crystal with high purity. X-ray diffraction anlysis shows that it belongs to orthorhombic system. The trace unreactive SO₂ as well as some by-product gases such as H₂S, COS and CS₂ has been detected in the tail gas. The method of restraint by-products is discussed.