Remodeling　of　ion　channels　is　an　important　mechanism　of　arrhythmia　induced　by　heart　failure　(HF).　We　investigated　the　expression　of　potassium　channel　encoding　genes　in　the　ventricles　of　rabbit　established　by　volume-overload　operation　followed　with　pressure-overload.　The　reversible　effect　of　these　changes　with　bisoprolol　was　also　evaluated.　The　HF　group　exhibited　left　ventricular　enlargement,　systolic　dysfunction,　prolongation　of　corrected　QT　interval　(QTc),　and　increased　plasma　brain　natriuretic　peptide　levels　in　the　HF　rabbits.　Several　potassium　channel　subunit　encoding　genes　were　consistently　down-regulated　in　the　HF　rabbits.　After　bisoprolol　treatment,　heart　function　was　improved　significantly　and　QTc　was　shortened.　Additionally,　the　mRNA　expression　of　potassium　channel　subunit　genes　could　be　partially　reversed.　The　down-regulated　expression　of　potassium　channel　subunits　Kv4.3,　Kv1.4,　KvLQT1,　minK　and　Kir　2.1　may　contribute　to　the　prolongation　of　action　potential　duration　in　the　heart　of　rabbits　induced　by　volume　combined　with　pressure　overload　HF.　Bisoprolol　could　partially　reverse　these　down-regulations　and　improve　heart　function.