Ten patients with multiple myeloma (two refractory and eight relapsing) received vincristine and adriamycin infusion therapy with oral high-dose dexamethasone (VAD regimen). Reduction in monoclonal immunoglobulin in serum exceeding 75 per cent was noted in three patients and reduction from 50 per cent to 75 per cent in four patients. Total response rate was 70 per cent. It was as high as the results reported in other countries. The responses to VAD regimen occurred rapidly. Most of them needed only one course. The side effects of VAD were not severe and were mainly reversible depression of leukocyte and infection of various kinds. All patients tolerated well. The probable mechanisms for increased response to VAD regimen are as follows. 1. Instead of administration as a bolus, vincristine and adriamycin were infused continuously and were given several times; therefore there was a prolonged unchanged concentration of the drugs in blood and exerting a possibly superior antitumor effect. 2. high-dose dexamethasone.