A　procedure　for　the　determination　of　iodide,　thiocyanate　and　perchlorate　ions　in　environmental　water　by　two-dimensional　ion　chronjatography　has　been　developed.　At　first　the　iodide,　thiocyanate　and　perchlorate　ions　were　separatedirom　interfering　ions　by　a　column　(Ion-Pac　AS16,　250　mm　x　4　mm).　The　iodide　ion,　thiocyanate　and　perchlorate　ions　were　then　enriched　with　an　enrichment/teolumn　(MAC-200,　80　mm　x　0.　75　mm).　In　the　2nd-dimensional　chromatography,　iodide　thiocyanate-and　perchlorate　ions　were　separated　and　quantified　by　a　capillary　column　(IonPac　AS20　Capillary,　250　mm　x　0.　4　mm).　The　linear　ranges　were　0.　05-100　μg/L　with,ic6rrelation　coefficients　of　0.999　9,　and　the　detection　limits　were　0.02-0.05　μg/L.　The　spiked)recoveries　of　iodide,　thiocyanate　and　perchlorate　ions　were　in　the　range　of　85.　1%　to　100.　1%.　The　relative　standard　deviations　of　the　recoveries　were　1.　7%　to　4.　9%.