The design and construction of artificial light-harvesting systems for solar energy conversion to chemical energy has been an active research field. A variety of molecules and materials have been used to mimic the function of the light-harvesting antenna. However, the improvement or regulation of the antenna effect of the existing artificial light-harvesting systems is less explored. Coordination polymers have aroused extensive concern due to their applications in light-harvesting and energy conversion. Herein, it is found that silver ion can dramatically enhance the emission of dye encapsulated in the coordination polymer nanoparticles (CPNs). The mechanism of Ag+-induced fluorescence enhancement is elucidated. Taking advantage of the effect of Ag+ ions, the regulation of CPN-based light-harvesting system by Ag+ is achieved for the first time. The antenna effect could be up to 2.3 times the original value by adding Ag+ ions. The present work provides a new approach to regulate the antenna effect of the light-harvesting system with the advantages of convenience, rapidity, low cost, and flexibility. (C) 2020 Elsevier Inc. All rights reserved.