The stability of aqueous Zn-ion batteries (AZIBs) is substantially compromised by anode interface side reactions and dendrite growth. These phenomena primarily stem from the non-uniform distribution of Zn2+ ions on the electrode surface as well as the detrimental effects of water. These phenomena primarily stem from the non-uniform distribution of Zn2+ ions on the electrode surface as well as the detrimental effects of water. Salicylic acid pentasulfonate (SC) was employed as an additive in 1 M ZnSO4 (ZSO) solution. Due to its high electronegativity, SC preferentially adsorbs on the Zn metal surface, disrupting the interfacial electric double layer structure. Therefore, the 3 mM SC + ZSO electrolyte enables the Zn//Zn symmetric cell to achieve a lifespan of ∼2900 h. Moreover, it endows the Zn//MnO2 full cell with excellent cycling stability, maintaining a stable capacity of 105 mAh g−1 after 1000 cycles at 1 A g−1. This work provides a feasible electrolyte modification strategy for enhancing the stability of AZIBs, laying a potential foundation for their further practical application.