©,　2015,　Editorial　Board　of　Journal　of　Xi＇an　Jiaotong　University(Medical　Sciences).　All　right　reserved.　Objective:　To　assess　the　therapeutic　effect　and　safety　of　radiofrequency　catheter　ablation　of　atrial　fibrillation.　Methods:　We　analyzed　the　clinical　data　of　47　patients　with　atrial　fibrillation　who　underwent　radiofrequency　catheter　ablation　between　March　2013　and　January　2008,　in　the　First　Affiliated　Hospital　of　Xi＇an　Jiaotong　University.　In　the　average　32　months＇　follow-up,　Holter　monitering　and　echocardiography　were　reviewed　for　the　left　atrial　diameter.　Results:　The　immediate　success　rate　of　catheter　ablation　for　atrial　fibrillation　was　82.6%.　The　long-term　success　rate　was　65%,　the　rate　of　paroxysmal　atrial　fibrillation　was　69.7%,　and　the　rate　of　longstanding　persistent　atrial　fibrillation　was　42.9%.　After　ablation,　the　left　atrial　diameter　were　markedly　reduced　compared　with　that　before　treatment　[(36.3±4.3)mm　vs.　(38.1±5.9)mm)　(P＜0.001).　The　patients　with　recurrent　atrial　fibrillation　were　older　than　those　without　recurrence,　their　left　atrial　diameter　was　bigger,　and　the　prevalence　rate　of　hypertension　was　higher　(P＜0.05).　The　average　atrial　fibrillation　load　was　14.9%　after　ablation　compared　with　46.1%　before　(P＜0.05).　Conclusion:　Radiofrequency　catheter　ablation　is　an　effective　and　safe　treatment　of　atrial　fibrillation,　especially　for　paroxysmal　atrial　fibrillation.　The　left　atrial　diameter　was　significantly　decreased　after　radiofrequency　catheter　ablation　compared　with　that　before　the　ablation.