In view of the low accuracy of EDTA complexometric titration method for the determination of zinc ion content in zinc ash in the factory, this paper compares the factory detection method with the method using xylenol orange as indicator for the determination of zinc ion content in zinc ash and finds out the reason for the high zinc content in the factory detection method. The results show that the factory detection method does not add masking agent to eliminate the interference of other ions when detecting zinc ions in the zinc ash, that is it does not cover the closed interference of Fe3+ and Al3+ to the indicator, while the xylenol orange method adds masking agent; the factory detection method is not standardized in the detection operation, such as the titration speed is too fast, it is easy to titrate too much, resulting in the detection of zinc ash the content of zinc ion is high.
