In　this　paper,　the　electrochemiluminescence　(ECL)　behavior　of　luminol/H2O2　system　in　the　presence　of　bromhexine　hydrochloride　(BrH)　was　investigated.　It　was　found　that　the　ECL　intensity　of　luminol/H2O2　system　on　a　platinum　electrode　could　be　intensely　quenched　by　BrH　owing　to　the　scavenging　superoxide　radical　ability　of　BrH,　and　therefore　the　sensitive　determination　of　BrH　was　possible.　Under　optimal　conditions,　the　quenched　ECL　intensity　was　linear　to　the　concentration　of　BrH　in　a　wide　range　of　0.08　to　500　μM,　with　a　detection　limit　of　0.02　μM　(signal-to-noise　ratio　(S/N)　=　3).　This　ECL　method　possessed　the　merits　of　rapid,　simple　and　sensitive,　and　was　successfully　applied　to　the　BrH　quantification　in　pharmaceutical　preparations　with　satisfactory　recoveries　of　91.0　±　4.0　to　106.5　±　3.4%.　The　possible　route　of　the　quenched　ECL　of　luminol/H2O2　in　the　presence　of　BrH　was　also　discussed.　Copyright　©　2018　John　Wiley　&　Sons,　Ltd.