Introduction: Atrial fibrillation (AF) is the most common sustained arrhythmia affecting humans. Several antiarrhythmic agents are effective for restoring and maintaining sinus rhythm, and selection of a particular drug depends on many factors, including the presence and type of underlying heart disease, concomitant illnesses, and renal or hepatic dysfunction. Ideally, the pharmacological treatment should have a high conversion rate or be able to control the improper high ventricular rate, being rapid in action and have a low incidence of side effects. Both amiodarone and propafenone have relatively high efficacy with the success rates ranging from 58% to 95%. Amiodarone has been administered (intravenously and orally) for the treatment of AF and the conversion rates ranged from 41% to 100% within the first 24 hours after administration, and showed to be relatively well tolerated. Propafenone has the advantage of acting rapidly and its efficacy in converting AF of recent onset to sinus rhythm has been documented.Aim of the work: To compare the efficacy and rapidity of recent oncet AF conversion by oral propafenone versus intravenous infusion of amiodarone. Patients and methods: We investigated 50 patients who suffered from recent onset AF within less than 48 hours. The patients were randomly divided into two groups the first group (group A) consisted of 25 patients in which amiodarone was administrated. The other group (group B) consisted of 25 patients in which propafenone was administrated.Results: The mean age was 52.88 ± 4.29 and 52.28 ± 5.69 years in group A and B respectively. There was no significant difference between both groups as regard the gender distribution. The number of hypertensive patients in group A was 9 patients (36%) while the number of hypertensive patients in group B was 10 (40%). The number of diabetic patients in group A was12 patients (48%) while the numbers diabetic patients in group B was 10 patients (40%). The number of patients with underlying structural heart disease in group A was 10 (40%)) while in group B was 8 (32%). In group A 18 patients had no previous episodes of AF, 4 patients had 1 previous episode, 1 patient had 2 previous episodes, 1 patient had 3 previous episodes and 1 patient had 4 previous episodes of AF. In group B 18 patients had no previous episodes of AF, 3 patients had 1 previous episode, 1 patient had 2 previous episodes, 2 patients had 3 previous episodes and 1 patient had 4 previous episodes of AF. 88% of patients in group A were successfully converted into sinus rhythm compared to 84% of patients in group B ( receiving propafenone). The time elapsed from drug administration till conversion of AF into sinus rhythm in group A was 9:07 ± 5:04 hours, while that of group B was 3:9 ± 1:54 hours, with p. value = 0.001 (highly significant). The mean left atrial diameter (L.A.D) (cm) of group A was 4.01 ± 0.34 cm, while left atrial diameter (L.A.D) (cm) of group B was 3.98 ± 0.35 cm. The mean left ventricular ejection fraction (LVEF) of group was 52 ± 10 %, while left ventricular ejection fraction (LVEF) of group B was 53 ± 8 %. The mean left ventricular end diastolic diameter (LVEDD) of group A was 55 ± 2 mm, while of group B was 53.7 ± 2.8 %. There was a negative and significant correlation between number of previous episodes of AF and success rate of conversion of AF in both groups. There was a negative and significant correlation between the presence of underlying heart disease and success rate of conversion of AF in both groups. There was a negative and significant correlation between the presence of diabetes mellitus and success rate of conversion of AF in both groups. There was a negative and significant correlation between the Left Atrial Diameter (LAD) and success rate of conversion of AF in both groups.Conclusion: Intravenous infusion of amiodarone as well as oral propafonone can be successfully used in cardioversion of AF into sinus rhythm. Intravenous infusion of amiodarone and oral propafonone are not only highly effective but also well tolerated drugs in management of recent onset AF. Time needed for conversion of AF into sinus rhythm using oral propafenone is significantly shorter than time needed by amiodarone to convert AF into sinus rhythm. Left atrial diameter is inversely proportionate to the success rate of AF conversion. The basal ventricular rate is inversely proportionate to the success rate of AF conversion. The presence of diabetes and hypertension had negative impact on conversion of AF into sinus rhythm.