This is a retrospective study on the care of odontogenic infections in admission patients with major bleeding disorders. The study was based on a series of 514 patients treated at Dong San Medical Center, Wonju Christian Hospital and Il San Health Insurance Hospital, from Jan.1, 2000, to Dec.31,2002. The obtained results were as follows : 1. The cardiovascular disease was the most frequent cause of the systemic diseases with major bleeding disorders, and liver disease, cerebrovascular disease and renal failure were next in order of frequency. But, there was the most frequent dental consultation in the liver disease, owing to the many odontogenic infectious diseases. 2. Male prediction (66.3%) was almost existed in the odontogenic infectious patients with major bleeding disorders. But, there was slight female prediction (53.4%) in the cardiovascular disease. 3. The most common age group of the odontogenic infectious patients with major bleeding disorders was the fifty decade(27.2%), followed by the forty, sixtyand thirty decade in order. 4. In the contents of chief complaints on the odontogenic infectious patients with major bleeding disorder, peak incidence was occurred as toothache (42.2%), followed by intraoral bleeding, ulcer pain, dental extraction in order. 5. In the diagnosis group of odontogenic infectious diseases, periodontitis, pulpitis and periapical abscess were more common. 6. In the treatment group of odontogenic infectious diseases, the most frequent incidence(44.2%) was showed in primary endodontic drainage(pulp extirpation, occlusal reduction and canal opening drainage) and followed by the incision and drainage, the medications and oral hygiene instruction, scaling, indirect pulp capping in order.