Adenoid cystic carcinoma(ACC) of the head and neck is relatively rare and is characterized by slow evolution, multiple recurrences, protracted clinical course, and distant metastases. This article presents its peculiar clinical course, pathologic type response to therapy and long-term treatment results by analyzing 67 patients treated from 1979 to 1991 at Seoul National University Hospital. The results were as follows : 1) The overall survival rates were 79% at 5 years and 43% at 10 years. 2) The disease-free survival rates were 46% at 5 years and 31% at 8 years. 3) The pathologic type and grade of ACC shows intimate correlation with the distant metastasis. 4) The patients treated with surgery and radiotherapy have better local control than the patients treated with either surgery alone or radiotherapy alone. 5) The overall survival rates and disease-free survival rates show a slow down sloping curve without plateau. Therefore a continuous follow-up of more than 10 years' period is necessary for patients with ACC.