Background: There was a study that overdrive atrial pacing with the atrial fibrillation (AF) suppression algorithm decreased symptomatic AF burden significantly in patients with sick sinus syndrome and AF. The aim of this study was to evaluate the short-term efficacy of AF suppression algorithm in patients with sick sinus syndrome and AF in korea. Methods: Symptomatic AF burden (percentage of days during which symptomatic AF occurred) was the primary end point. Patients with sick sinus syndrome and AF underwent pacemaker implantation (DDDR with the algorithm) and they were observed prospectively at least six month follow-up (algorithm on for 3 months and then off for 3 months) Results: Nine patients were included this study. The average age of patients was 69.0 (60.5-77.0; median, interquartile range) years. Five patients were men and four patients were women. Antiarrhythmic drugs were used only one patient who was 84 year old woman. AF burden with the algorithm off for first 3 months was 25.0 (5.5-38.5; median, interquartile range) %, and AF burden with the algorithm on for next 3 months was 24.0 (1.25-42; median, interquartile range) %. Conclusion: AF burden with the algorithm on for 3 months, compared with algorithm off for first 3 months, was not decreased significantly, because patients might be too small to assess statistical analysis and patient with paroxysmal AF which was converted into approximately permanent AF was included in this study.