From November 2005 to November 2008, a total of 20 cases of relapsed/refractory MM were treated with bortezomib combined with methylprednisolone in our department. There were 13 male and 7 female cases, median age 57.5 (42-76) years, and median time to disease diagnosis was 28 (2-82) months. Clinical typing: 6 cases of IgG, 5 cases of IgA, 2 cases of IgD, 6 cases of light chain, and 1 case of biclonality. The Durie-Salmon stage at diagnosis was: stage IIIA in 14 cases and stage IIIB in 6 cases; the ISS stage was: stage I in 11 cases, stage II in 3 cases and stage III in 6 cases. The median percentage of myeloma cells before treatment was 0.21 (0.015 to 0.775). All patients received at least 2 courses of standard chemotherapy (including melphalan regimen or VAD regimen, etc.) with a median of 10 (2 to 22) courses of chemotherapy; 18 patients had received thalidomide and 3 patients had received autologous hematopoietic stem cell transplantation; 4 patients had extramedullary plasmacytoma and had received radiotherapy. All patients were treated with bortezomib 1.75 mg [(0.9-1.1) mg/m2] administered on days 1, 4, 8, and 11, and methylprednisolone 40 mg (4 patients), 80 mg (2 patients), 120 mg (2 patients), 200 mg (7 patients), and 300 mg (5 patients) in combination on days 1, 4, 8, and 11. 3 weeks was the duration of treatment, and at least 2 courses of treatment. After 2 courses of bortezomib treatment, the efficacy was evaluated in 19 patients; CR in 5, VGPR in 2, and PR in 8, with an overall efficacy rate of 78.9%; SD in 2 and PD in 2. Of the 11 evaluable patients after 4 courses of treatment, 6 had CR, 1 had VGPR, and 4 had PR. Of the 5 patients who completed 6 courses of treatment, 3 had CR, 1 had VGPR, and 1 had PR. The four patients with extramedullary plasmacytoma had significantly smaller extramedullary plasmacytomas, and two cases had complete disappearance.