A　rapid,　easy　and　reproducible　capillary　electrophoresis　(CE)　method　for　the　simultaneous　determination　of　allantoin,　choline　and　arginine　in　Rhizoma　Dioscoreae　was　developed　first　time.　Under　the　optimum　condition,　the　three　analytes　could　be　well　separated　within　5　min　in　a　70　cm　(60　cm　effective　length)　x　75　mum　i.d.　capillary.　The　relative　standard　deviations　for　both　migration　time　and　peak　height　were　less　than　3.20%.　The　linear　response　range　was　5.0-150,　0.9-100　and　1.0-200　mug/ml　for　arginine,　choline　and　allantoin,　respectively.　The　detection　limit　of　three　components　was　2.0,　0.4　and　0.5　mug/ml　for　arginine,　choline　and　allantoin,　respectively.　Contents　of　arginine,　choline　and　allantoin　in　the　crude　drug　of　Rhizoma.　Dioscoreae　could　be　easily　determined　by　the　proposed　method　with　satisfactory　results.　(C)　2004　Elsevier　B.V.　All　rights　reserved.