Method for detecting content of active bacteria

The invention discloses a method for detecting the content of active bacteria and in particular relates to a method for detecting the content of active bacteria through combined use of CTC dye (5-cyano-2,3-ditolyl tetrazoliumchloride) dyeing and a flow cytometry, and the method is called as CTC-flow cytometry method or CTC-FCM method for short. The first method for detecting the content of the active bacteria comprises the following steps of: co-incubating CTC dyes and a liquid sample to be detected, and detecting the content of the active bacteria in the liquid sample to be detected through the flow cytometry. The sensitive detection instrument (namely the flow cytometry) is used for detecting faint labeled cells and determining optimal experiment conditions, thereby greatly improving the accuracy of the detected active bacteria, and fulfilling the aim of accurately and rapidly detecting active pathogenic bacteria. The method is rapid, easy and convenient, has a broad-spectrum recognition property, can accurately and rapidly detect the active pathogenic bacteria and can be used for detecting the active pathogenic bacteria in an environmental sample.