The aim of this study was to compare the adsorption efficiency of lactic acid onto activated carbon and Amberlite IRA-67, and to define the adsorption isotherms. Activated carbon is a well-known industrial adsorbent and was used in this study; Amberlite IRA-67 is a weakly basic polyacrylic resin with a tertiary amine functional group. Adsorption efficiencies of activated carbon and Amberlite IRA-67 were compared with respect to their percentage of removal acid. The result of this comparison is that Amberlite IRA-67 is more efficient than activated carbon. Each of these adsorbents is in compliance with both the Freundlich and Langmuir isotherms.