Rare-earth elements in rock reference samples were analysed by ion chromatography using α-hydroxyisobutyric acid (α-HIBA) as an eluent. The technique employs the chelating agents to permit the separation of individual REEs as cationic complexes. Use of α-HIBA is more appropriate for the elution of REEs than of oxalic acid. The reasons are as follows: 1) The heavier REE abundance in geologic samples is lower than lighter one, so for the purpose of decreasing the tailing, it is important to elute REE in order of the lower abundance i.e. heavy REE. 2) The baseline is steadier, and 3) the separation of individual REEs is better than that by the techniques using oxalic acid. By this method, however, it is impossible to obtain data for Dy, due to interference by Y.
     Providing that more sufficient care is taken over preparations of standard solution and eluent in purpose of separation of individual REEs, the accuracy will be improved and ion chromatography can be one of the available techniques for REE analysis of geological samples.