Abstract: It was found that in an alkaline medium of KOH,the chemiluminescence (CL) reaction between luminol and H2O2 was catalyzed by the complex formed by Cr(Ⅵ) with 8-hydroxyquinoline,and that linear relationship between the intensity of CL and the concentration Cr(Ⅵ) ion was kept in the range of 3.0×10-3 to 4.0×10-2 mg·L-1,having its linear regression equation as ICL=3.6+1.68×106C (g·L-1) with correlation coefficient of 0.999.Detection limit of this method was found to be 1.2×10-3mg·L-1 for Cr(Ⅵ),under the condition of K=3 and confidential level of 99.6%.Test of precision was made at the concentration level of 2×10-2mg·L-1 of Cr(Ⅵ) for 11 multiplicate determinations,and the RSD′s obtained was 2.8%.In the application of this method to the determination of Cr(Ⅵ) in samples of calcium propionate and animal protein powder,results obtained were in consistency with the results obtained by photometry.RSD′s (n=5) found were less than 3.2%,and recovery tested by the standard addition method gave results in the range of 96% to 105%.A brief discussion on the reaction methanism was also given.