Releases of silver ions (Ag+) from silver nanoparticles (AgNPs) has a great impact on many of their functional processes, especially the antimicrobial potency and ecotoxicity. In this study, we employed for the first time a fluorogenic Ag+ sensor, tetrazole-functionalized tetraphenylethylene derivative 1 (TEZ-TPE-1), to investigate the time-dependent dissolution behavior of some typical classes of AgNPs and silver nanowires in aquatic environments. Real-time and quantitative monitoring of the Ag+ release was achieved by using the proposed sensing method, which agreed well with the conventional ICP-MS detection method. The system reported herein therefore offers a simple and straightforward approach and can be used to study the role of released Ag+ from metallic AgNPs, which is critical in antibacterial applications.