Equally important to the design of the electrode materials is the selection of the proper electrolyte. The capacity of MOFs and MOF composites in organic and aqueous electrolytes always varies, and the electrolyte also affects the working voltage. The potential range of an aqueous electrolyte is typically highly dependent on the pH value because both the potential oxygen evolution reaction and the hydrogen evolution reaction are sensitive to pH. When using a neutral electrolyte, a broader voltage range for materials based on carbon and metal oxides is demonstrated by the higher overpotentials offered for the oxygen evolution reaction and the hydrogen evolution reaction as compared to electrolytes that are acidic or alkaline. However, MOFs' aqueous stability needs to be improved. In contrast, clean MOFs are better suited to organic electrolytes or ionic liquids with redox-active species. High MOF stability in the electrolyte under polarization is also necessary for this. The optimal electrolyte for the corresponding electrode materials still needs research.