We report a case of multiple myeloma involving the mandible and gingiva. A 71-year-old manvisited our hospital on June 9, 1999 because of gingival swelling and continuous bleeding from the leftmandibular molar. Clinical examination revealed a soft, smooth, partially erosive mass in the lingualgingiva of the mandible. Slight, but continuous bleeding was observed in the erosive area. The patient appearedto have multiple myeloma of the mandible. On August 20, he had pain during biting, tooth mobility, gingival bleeding from the left mandibular molar, and hypoesthesia of the lower lip. On August 31, thepatient's swollen gingiva was resected, and the first and second molars were extracted from the left sideof the mandible. Histologic examination was also performed. No post-extraction hemorrhage occurred.For almost 4 months after extraction, the patient showed no evidence of oral multiple myeloma, but diedon December 26.