Despite　its　low　equipment　cost　and　simple　design,　as　one　of　the　sensitive　detectors　for　CE,　the　chemiluminescence　(CL)　detector　was　less　developed　compared　to　the　detectors　of　MS　and　LIF.　The　main　reasons　were　the　limitation　of　CL　reagents,　the　repeatability　problems　and　the　relatively　low　sensitivity　compared　to　LIF.　In　this　paper,　a　highly　sensitive　CE-CL　detection　system　was　developed　for　detection　of　some　enkephalin-related　peptides　labeled　with　acridinium　ester.　A　new　detection　interface　was　designed　for　CE　with　CL　detection　of　acridinium　ester　and　its　labeled　analytes.　The　interface　included　two　sections:　one　was　used　to　acidify　the　capillary　oufflow　so　that　the　corresponding　acridinium　pseudo-base　form　can　be　changed　into　acridinium　ester　form　by　adding　excess　acid　to　the　system;　the　other　was　designed　to　provide　a　suitable　solution　to　produce　the　CL　from　acridinium　ester.　The　effect　factors,　such　as　pH,　the　concentration　of　reaction　reagents　and　the　flow　rates　of　the　reagents,　were　investigated.　The　results　showed　that　acridinium　ester　had　similar　CL　properties　in　this　interface　when　pH　values　of　CE　BGE　were　changed　from　2.0　to　10.8.　The　interface　was　used　to　detect　acridinium　ester　and　three　acridinium　ester-labeled　enkephalinrelated　peptides,　the　corresponding　LODs　were　found　to　be　in　the　attomole　range.　This　CL　detection　system　proved　to　be　of　high　sensitivity,　good　repeatability,　and　relatively　low　cost.