Soya bean milk was given orally in doses of 150 ml second-hourly (7 a.m. to 11 p.m. daily) to 10 Chinese subjects with proven gastric ulcer for two weeks. The control group consisted of 10 Chinese subjects with proven gastric ulcer who did not receive soya bean milk therapy. All were inpatients and were given bed rest. Gastric ulcer healing was assessed endoscopically with a duodenofibrescope. Endoscopic visualization and colour photography of the ulcer crater were undertaken just before and after two weeks of treatment. In the soya bean milk group, complete healing was seen in two cases, considerable healing in four cases, slight healing in two cases, and no healing in two cases. In the control group, complete healing was seen in no cases, considerably healing in three cases, slight healing in four cases, and no healing in three cases. The mean ulcer healing grade was 1.600 in the soya bean milk group as compared with 1.000 in the controls. The difference was not statistically significant. There was no significant difference between the two groups in the initial ulcer size, age and sex distribution. Although the effect on gastric ulcer healing was not significant, soya bean milk has been shown to be effective in the relief of peptic ulcer pain.