Abstract: A plant test of co-processing of DDT waste in cement kiln was carried out. The destruction removal efficiency (DRE) of DDT, the stack emission state and their effects on cement quality were studied by controlling different DDT waste feeding rates. The results suggested that the DRE of DDT could be up to 99.999 996 2% when DDT waste feeding rate was controlled at less than 1.0 t/h, and the average PCDD/Fs concentration of flue gas was far lower than the national limit of 0.1 ng I-TEQ/Nm³. Furthermore, the co-processing of the DDT waste had no remarkable negative influences on either the flue gas emission or the cement product quality.