Practical application of aqueous Zn‐ion batteries (AZIBs) is significantly limited by poor reversibility of the Zn anode. This is because of 1) dendrite growth, and 2) water‐induced parasitic reactions including hydrogen evolution, during cycling. Here for the first time an elegantly simple method is reported that introduces ethylene diamine tetraacetic acid tetrasodium salt (Na4EDTA) to a ZnSO4 electrolyte. This is shown to concomitantly suppress dendritic Zn deposition and H2 evolution. Findings confirm that EDTA anions are adsorbed on the Zn surface and dominate active sites for H2 generation and inhibit water electrolysis. Additionally, adsorbed EDTA promotes desolvation of Zn(H2O)62+ by removing H2O molecules from the solvation sheath of Zn2+. Side reactions and dendrite growth are therefore suppressed by using the additive. A high Zn reversibility with Coulombic efficiency (CE) of 99.5% and long lifespan of 2500 cycles at 5 mAh cm−2, 2 mAh cm−2 is demonstrated. Additionally, the highly reversible Zn electrode significantly boosts overall performance of VO2//Zn full‐cells. These findings are expected to be of immediate benefit to a range of researchers in using dual‐function additives to suppress Zn dendrite and parasitic reactions for electrochemistry and energy storage applications. A dual‐function additive, ethylene diamine tetraacetic acid tetrasodium salt (Na4EDTA), is applied in a ZnSO4 electrolyte to boost the reversibility of Zn anodes via electrolysis inhibition and desolvation promotion. These characteristics originate from the high adsorption ability of EDTA on the Zn surface, and strong interaction with Zn2+ hydrated ions. The EDTA‐containing electrolyte endows high Coulombic efficiency, stable voltage profiles and stable cycling performance to VO2//Zn cells.