Necrotizing sialometaplasia (NS) was defined by Abrams et al. in 1973 as a reactive necrotizing inflammatory process involving minor salivary glands of the hard palate. Before that recognition, many patients with this condition had been improperly treated because of its clinical and histologic resemblance to malignancy such as mucoepidermoid carcinoma and squamous cell carcinoma. We report two cases of necrotizing sialometaplasia. One case involved a 58-year-old male who had an ulcerative palatal lesion exposing underlying bone which has the typical features of the above mentioned condition. Another case involved a 59-year-old male who developed a necrotizing sialometaplasia in association with a dome-shaped palatal swelling which was proved as an adenoid cystic carcinoma after operation biopsy.