A　capillary　electrophoresis　method,　using　field-amplified　sample　injection　(FASI),　was　developed　for　separation　and　determination　of　some　β2-agonists,　such　as　cimaterol,　clenbuterol　and　salbutamol.　The　optimum　conditions　for　this　system　had　been　investigated　in　detail.　The　precision　of　the　migration　time,　peak　height　and　accuracy　were　determined　in　both　intra-day　(n　=　5)　and　inter-day　(n　=　15)　assays.　Under　the　optimum　conditions,　the　detection　limits　(defined　as　S/N　=　3)　of　this　method　were　found　to　be　lower　than　2.0　ng/mL　for　all　of　these　three　β2-agonists,　which　were　much　lower　than　that　of　the　conventional　electro-migration　injection　method,　the　enhancement　factors　were　greatly　improved　to　be　30-40-fold.　Such　lower　detection　limit　lets　this　method　to　be　suitable　for　determination　of　above-mentioned　β2-agonists　in　the　urine　sample.　The　mean　recoveries　in　urine　were　higher　than　96.2%,　95.6%　and　95.3%　for　cimaterol,　clenbuterol　and　salbutamol,　respectively,　with　relative　standard　deviations　lower　than　3.5%.　©　2006　Elsevier　B.V.　All　rights　reserved.