Background and Objectives： Adenoid cystic carcinoma (ACC) is an aggressive, often indolent tumor, with a high incidence of distant metastasis (DM). Relatively little has been written about the factor that influence distant spread and subsequent survival because it is uncommon and has protracted clinical course. We attempted to reemphasize the biologic behavior of ACC by investigating the relationship between the clinical features and prognosis. Materials and Methods : We have retrospectively studied 24 determinate patiens who received definitive treatment in our hospital between 1984 and 1995 for ACC in all salivary sites. Inclusion criteria were no prior treatment elsewhere other than excisional biopsy and eligibility for follow-up of at least 5 years. Variables assessed for their impact on distant metastasis included age, gender, size, node status, stage, histologic pattern, locoregional treatment failure. Results : Treatment failure occurred in a total of 16 of 24 determinate Patients (64%), 12 of whom had DM (50%). This was usually associated with locoregional recurrence (8 patients), but DM was the only indication of failure in 4 whose primary tumor was controlled. Of the 12 patients with known DM, the lung was recored as the only involved site in 7 Patients, lung was involved in addition to other sites in 1, bone and liver metastasis occurred in 2 respectively. Disease-free intervals varied from 3 month to 14 years (median 3 years). The only significant factors influencing survival were the size of the primary tumor, locoregional recurrence. Conclusion : The high incidence of DM with locoregional failure confirms the importance of aggressive initial surgery. combined with irradiation, for high-stage tumors or involved surgical margins. Large tumor size and locoregional recurrence, rather than microscopic appearance, were predictive of DM.