Pathogen infection and cancer are the two major human health problems. In this work, we achieved an organic salt photosensitizer (PS), called 4TPA-BQ with aggregation-induced emission feature via one-step reaction. Owing to the aggregation-induced reactive oxygen species generation effect and sufficient small ΔEST, 4TPA-BQ shows a satisfactorily high 1O2 generation efficiency of 97.8%. In vitro and in vivo experiments confirmed that 4TPA-BQ exhibited potent photodynamic antibacterial performance against ampicillin-resistant Escherichia coli with good biocompatibility in a short time (15 min). When the incubation time persisted long enough (12 h), cancer cells were ablated efficiently, leaving normal cells essentially unaffected. This is the first reported time-dependent fluorescence-guided photodynamic therapy in one individual PS for ordered and multiple targeting by varying the external conditions. This can update the design principle of efficient PSs in potential clinical applications.