Endogenous hydrogen peroxide in vivo is related to many diseases, including cancer, diabetes, cardiovascular disease, and neurodegenerative disorders. Although many probes for detection of HO have been explored, rapid response probes are still expected for in vivo application. Here, a new probe (PAM-BN-PB) was designed based on an intramolecular charge transfer (ICT) process with three parts: phenanthroimidazole, benzonitrile, and phenyl boronate. By modulation ICT process of PAM-BN-PB, HO in solution systems can be detected with good selectivity. The exogenous and endogenous HO in normal living cells, ischemia-reperfusion injury cells, and animals all can be imaged by PAM-BN-PB.