Tooth extraction is a common procedure in dental clinic. However, wound bleeding after tooth extraction always makes patients feel more panic and patients would have less confidence in doctors. Effective ways to decrease the above emergency cases are careful preoperative evaluation, less perioperative trauma, and proper postoperative education. The samples of this study are the dental patients of emergency department of Chi-Mei Medical Center. We collected 163 patients who experienced wound bleeding after tooth extraction (including impacted tooth surgery) and went to emergency department for help during November, 2006 to December, 2010. We took retrospective analysis of the patients' general data and treatment course, and discussed the risk factors and management of wound bleeding after tooth extraction.