As we know, iodide plays essential roles in neurological activity and thyroid gland function. Various methods have been proposed to monitor the iodide in food and drugs such as UV–vis absorption[36,37], fluorescence [38–44], electrochemical method [45–47] and chromatography [48,49]. These methods have advantages such as high sensitivity and good selectivity, but require expensive instruments or time consuming procedures. However, the newcolorimetric method proposed here, is a novel, simple and stable detection of iodide with both high sensitivity and good accuracy. We believe that his new colorimetric will find its future.