Herein, we designed a potent ClO− probe named ETMC, which exhibited aggregation-induced emission (AIE) characteristic in solid state and water/EtOH binary solvent. Probe ETMC exhibited an colormetric from yellow to blue and ratiometric response to ClO− with high selectivity and sensitivity, and a low detection limit of 3.66 × 10−7 M. Moreover, probe ETMC could be applied to visibly and quantitatively detect the different concentraction of ClO− in test paper. Importantly, probe ETMC could effectively detect endogenous and exogenous ClO− in living A549 cells by an outstanding ratio signal change. Also, the sensing mechanism of probe ETMC for ClO− was confirmed by FT-IR, 1H NMR, HRMS, DLS, TEM and DFT calculation.