Abstract: In orde to discover the form migration of Cr during co-processing hazardous wastes contained Cr,Na₂CrO_4was added to the raw material simulation Cr-containing material into the kiln (the mixing ratio is 0.048%(w)). The raw material mixing with Na₂CrO_4was calcined at different temperatures. The residual rate of Cr was studied by digestion of samples calcined. The chemical forms of Cr were obtained by X-ray absorption near edge structure (XANES). The results showed that, the conditions of Cr clinker residual rates were 88.2%, 70.7%, 73.7%, 67.2%, 69.5% and 67.8% at temperatures of 900-1450℃. The kiln tail of temperature was 1050-1100℃ and was closed to 1100℃, at the temperature of 1100℃. Therefore, it reduced the disposal of Cr during co-processing waste in the cement kiln adding waste at the kiln tail. Cr mainly existed in the forms of CrO₃,Cr₂O_3and CaCrO_4under the conditions of 900-1450℃. In addition, K₂Cr₂O_7was produced under the condition of 1000℃ and K₂CrO₄was produced under the conditions of 900,0,1200and 1300℃. Cr entered into the main cement mineral combined with other substances to generate more complex Cr-containing substances such as Ca₄Al₆O₁₂CrO_4and this material was mainly in the form of CrO_3and Cr₂O₃under the ranges from 1100℃ to 1450℃.