Adenoid cystic carcinoma(ACC) is the second most common malignant neoplasm in the salivary gland. In spite of ACC shows slowly growing nature, it is sometimes highly detrimental that it readily invades adjacent tissues and metastasize to distant organs at the early stage of disease. Hence, treatment outcome may be misfortunate due to wide regional infiltration, pathognomonic perineural spread and the tendency of hematogenous metastasis. We present a unusal case of ACC of the scalp in which the patient initially presented with bumpy mass of the scalp who had been diagnosed as the primarily developed ACC of the right hard palate that extended to infratemporal fossa, nasal cavity, and paranasal sinuses and had been treated by total excision and post-operative chemotherapy and radiation therapy for 10 years ago. Although this lesion occured at the scalp, which is a frequent site of primary dermatologic ACC, its histomorphology was the same with that of previous tumor. Complete clinical examination showed no recurrence sign at the primary site and suggested the scalp as a sole treatment failure site. Accordingly, it would be reasonable to consider the present case as either a scalp metastasis or a second primary lesion of salivary gland ACC.