Objective: Complete atrioventricular (AV) block is a rhythm disorder that can result from various causes. The aim of this study was to define etiological factors, clinical features, pacemaker needs, in-hospital mortality rates and factors affecting these parameters in the patients with complete AV block. Methods: For this aim, 191 consecutive patients admitted to the hospital with complete AV block or who developed AV block during their hospital course between January 1999-September 2002 were included into the study. Results: The most common underlying cause of AV block was found to be the ischemia, which was followed by unknown etiology and iatrogenic complete AV block. The most common cause of in-hospital mortality was ischemic (especially acute) heart disease. No etiological factor for complete AV block was found in most of symptomatic patients presented with syncope. In patients with ischemic complete AV block, mortality and syncope rates were found to be high, especially in patients with multivessel disease. Permanent pacemaker was implanted in 76 of 191 patients with complete AV block and the significant portion of these patients were those without an etiological cause. Conclusion: Thus, it is revealed that factors affecting mortality in patients with complete AV block are acute myocardial infarction and age while other clinical parameters and pacemaker implantation had no effects on mortality.