Mass-transfer coefficient for anion exchange was determined for commercially available strong-base anion exchange resin of Cl type in use to remove nitrate in water. Experiments were performed over an initial solution concentration range from 5 to 50ppm nitrate and temperature range from 283 to 323k in 2L batch reactor. Effective diffusion coefficient was obtained in the range from 9.67×10＾8 to 1.67×10＾6㎠/sec for initial concentration change, and from 6.09×10＾7 to 3.98×10＾6㎠/sec for reaction temperature change. Activation energy during the diffusion was calculated as 36 kcal/mol.