Among patients with di seases of dental 01' oral & maxillol'acial a reas, those who have pathologic lesions ta ke upon a considerable part of these pat ients , The accurate diagnosis is importa nt for the treatment of them Oral and max illofacial lesions may have specifi c characteristics associated with tooth, oral mucosa‘ sali vary gland itself and its devel opmental process, For histopathologic diagnosis of oral and maxill ofacial lesions . pa thologist s hould unde rstand pathogenesis, clinical features, radiographic appearance, treatment, and prognosis of the lesions. [n the hos pital that had oral surgeons on staff, but not an oral pathologist, they sent the pa thologic samples and requ ested the delïn itive diagnosis t。 the oral pathologist worked in th e other dental college hos pita l, Recently, however, it had been impossible for some reasons 80 they sent the samples to general pathologists worked in private clinical laboratory center, 8ince then, oral surgeons and their pati ents were occasionally suffered I'rom unreliabl e and even inacc ura te diagnoses and improper treatments We would like to review the cases that general pa thologists made wrong diagnosis and emphasize the necessity and importance of oral pathologists for oral surgeons.