We investigated 248 patients who were diagnosed as malignant tumor in the department of Oral and maxillofacial Surgery of Kyungpook National University from 1999 to 2006, and following results were obtained. 1. Among 248 patients who have malignant tumor, 164 were men and 84 were women, which made the ratio of male to female 1.95:1. 2. The average age of oral cancer patients was 58.3. 3. As of the primary origin site, lower alveolus and gingiva were the greatest with 70 cases(28.2%), followed by tongue(l6.9%), upper alveolus and gingiva(14.9%), palate(13.7%), mouth floor(9.7%), buccal mucosa(4.8%), retromolar trigone(4.4%), Mx. & Mn. bone(3.2%) and lip(2.8%). 4. As of histologic distribution, squamous cell carcinoma was the greatest with 170 cases(68.6%), followed by sarcoma with 17 cases(6.9%), adenoid cystic carcinoma with 17 cases(6.9%), malignant lymphoma with 15 cases(6.0%), mucoepidermoid carcinoma with 13 cases(5.2%), metastatic carcinoma with 6 cases(2.4%) and malignant melanoma with 4 cases(1.6%). 5. Period between recognition of the symptom and the first visit to hospital was less than 3 months for 58.9% of the patients, and more than 3 months for 41% of the patients. 6. Investigation of whether the patients drink or smoke revealed that the number of non-smoking and non-drinking patients was 63 among 170 patients(37.0%) that were able to investigate. The number of patients who smoke only was 29(17.1%) and both drinking and smoking patients were 78(45.9%). 7. In clinical stage order, Stage IV(61.7%) was found th be the largest, followed by stage I(17.2%), stage II(13%) and stage III(7.8%). 8. The 5-year survival rate of the entire oral cancer patients appeared to be 57.7%. The survival rate was higher in younger group and women had higher survival rate but there was no statistical significance to this. In the aspect of stage, the survival rate was Stage I, Stage II, Stage IV and Stage III in decreasing order. The order according to T classification was the same. In N classification, patients with N0 had the highest survival rate and the survival rate decreased in the order of N1 and N2. Survival rate was especially low in patients with N2.