Background: The aim of this study was to compare the incidence of postoperative secondary hemorrhage for tonsillectomy and submucosal uvulopalatopharyngoplasty (smUPPP). Materials and Methods: In this retrospective case series, the medical records of 404 patients who underwent tonsillectomy with unipolar electrocautery and smUPPP at our institution between January 2001 and December 2010 were reviewed. The patients were divided into two groups: Group 1 (198 patients) underwent tonsillectomy; Group 2 (206 patients) underwent smUPPP. Main outcome measures were incidence of bleeding or complications after tonsillectomy and smUPPP and the need for revision surgery. Results: The mean age of Group 1 patients was 38.1 (±2.58) years and that of Group 2 was 37.7 (±2.25) years. Males were 51.3% of Group 1 and 46.7% of Group 2. No statistically significant difference in age or gender distribution was found between Groups 1 and 2. The incidence of secondary, delayed hemorrhage was 5.05% (10 patients) in Group 1 and 1.45% (three patients) in Group 2 (P = 0.05). The incidence of delayed hemorrhage requiring surgical treatment was 4.54% (nine patients) in Group 1 and 0.97% (two patients) in Group 2. Conclusion: In adults, smUPPP, which includes tonsillectomy, has a lower incidence of postoperative delayed hemorrhage than does tonsillectomy with unipolar cautery.