Multiple myeloma is a malignant plasma cells proliferation in the bone marrow leading to a monoclonal immunoglobulin hypersecretion. The survival duration of this disease ranges usually from 2 to 3 years. However, as this reported case, a long-term survival remains possible. A 29 year old woman was admitted to the internal medicine department for bone pain, weight loss and pathologic fractures. The clinical examination revealed an anaemia, a spinal compression (D10) and atrophia of quadriceps and gluteus muscle. The radiologic findings observed were multiple fractures. The bone marrow aspiration confirmed the plasmocytosis greater than 50%, with immature plasma cells and other lineages rarefication. The disease belonged to the stage III A of the Salmon and Durie classification. Chemotherapy with melphalan associated to prednisone was started with a two to three months biological and clinical follow-up. This treatment allowed 12 years survival. Because of this variety, the search for new prognostic factors would be relevant.