The glycerol test is one of the most important diagnostic tests for Meniere's disease. But patients usually experience nausea, vomiting and gastrointestinal discomfort after peroral ingestion of glycerol. Furthermore the absorption of glycerol through gastrointestinal mucosa is variable. The purpose of this study is to observe hearing changes and compare the effectiveness between the one hour infusion and two hour infusion methods after intravenous infusion of glycerol in Meniere's deseased and in normal subjects. Pure tone thresholds were measured before and at 30, 60, 90 and 120 minutes during intravenous infusion of 10% glycerol 500ml in 20 Meniere's disease patients and 20 people in the normal control group. The following results were obtained : 1) Hearing improvements were noted in 13/20 ears (65%) of Meniere's disease patients and 11/40 ears (27.5%) of normal subjects (p<0.05). 2) In the Meniere's diseased group, there was no significant difference in hearing improvement between 1 hour (60.0%) infusion and 2 hour (65.0%) infusion (p>0.05). 3) The hearing improvement of these in Meniere's disease group was present mainly at 250 and 500 Hz. 4) No significant side effects were observed after glycerol infusion.