The dissolution kinetics of silver nanoparticles (Ag NPs) to Ag + ions is a critical factor determining the toxicity of silver nanoparticles. In this work, a solid-contact Ag +-selective electrode (Ag +-ISE) is fabricated and used to monitor the dissolution of Ag NPs. Ordered mesoporous carbon is compared with disordered mesoporous carbon as the solid-contact material for the Ag +-ISE. The ordered mesoporous carbon based solid-contact Ag +-ISE shows a linear potential response in the range of 1.0 × 10 −6-1.0 × 10 −3 M AgNO 3 with the slope of 55.6 ± 0.8 mV/dec (n = 7) and the detection limit of 10 −6.8 M. The solid-contact Ag +-ISE is used to monitor the concentration changes of Ag + during spontaneous dissolution of Ag NPs in deionized water, and the dissolution kinetics of Ag NPs is consistent with that obtained by inductively coupled plasma-mass spectrometry (ICP-MS). Stimulated dissolution of Ag NPs induced by addition of H 2O 2 to the Ag NP solution is also investigated by the proposed solid-contact Ag +-ISE. This work provides a fast tool for charactering the dissolution of Ag NPs to Ag + in real time, which is important for studying the toxicology of nanoparticles.