Meso-phosphino-substituted BODIPY probes were developed for concise and rapid detection of hypochlorite (ClO-). Interestingly, the probe BPgave a turn-on fluorescence response by shutting the photoinduced electron transfer (PET) effect and extending the coplanar conjugated π-system. In contrast, the probeTMBPshowed a colorimetric response toward ClO-. The key role of the steric repulsions was revealed to be for altering the electronic distribution of the BODIPY core, resulting in these obviously different responses. Finally, the probeBP, with high selectivity and sensitivity toward ClO-(LOD = 1.9 nM; response time, <15 s), was further employed in imaging the variations of exogenous and endogenous hypochlorite (ClO-) in living RAW 264.7 cells and mouse inflammation models. If wisely utilized, this strategy with meso-phosphino BODIPY dyes may serve as a powerful platform for the preparation of novel chemosensors.