Abstract To change permselectivity between two anions through anion-exchange membranes in electrodialysis, the hydrophilicity of the anion-exchange membranes was increased by impregnation of hydrophilic compounds, ethylene glycols with varying molecular weights, into the membranes. Ethylene glycols have good affinity to the anion-exchange membranes and were selectively impregnated into a domain where anion-exchange groups exist. The change in the transport numbers of bromide, fluoride, sulfate, and nitrate ions relative to chloride ions was evaluated in the presence of the glycols (because the glycols dissolved from the membrane matrix to the salt solutions, electrodialysis was carried out using the salt solutions containing the glycols). Permeation of the strongly hydrated anions, fluoride and sulfate ions, was increased compared with chloride ions, and permeation of the less hydrated anions, bromide and nitrate ions, became difficult to achieve through the membranes in the presence of ethylene glycols. This was due to the increase in the uptake of more hydrated anions into the membrane and not due to the change in mobility ratio between anions through the membrane. Increasing the hydrophilicity of the anion-exchange membranes was an effective method for changing the permeation behavior of anions through membranes in electrodialysis.