Objective: To report and discuss the clinical and histopathological findings of a case of multiple myeloma in the jaw region. Case Report: A 58 year old female patient came to UNIPAR Dentistry School complaining of "increased volume on the left side of the face". On physical examination it was observed intact mucosa with buccal cortical expansion in the region of the teeth 34/35/36 and asymptomatic. Radiographic examination revealed a radiolucent area approximately 25 mm in diameter. An incisional biopsy was performed and the histopathological diagnosis was suggestive of plasmacytoma/multiple myeloma, and after finding other lesions it was confirmed as multiple myeloma. The patient was then referred to a hematologist who, together with the oncologist, established the treatment. Conclusion: Although treatment is a medical responsibility, the dental surgeon has an important role in the early diagnosis of this disease, since some of its first clinical and radiographic findings are related to the maxillomandibular complex.