Surface electrogastrograms were recorded in 95 patients. There were 6 groups of patients: chronic superficial gastritis (20), chronic atrophic gastritis (20), duodenal ulcer (20), gastric ulcer (17), gastric cancer (8), and diabetes mellitus (10). Electrogastrographic examination was continuously carried out for 60 minutes both in fasting and postprandial state. (1) During the fasting state, in 72% of the cases, there was a 50% to 100% change in the mean of the amplitude among six 10-minute periods of recording. (2) In 23 cases (25%), there was no amplitude increase in the postprandial electrogastrogram. Feeding caused an increase in amplitude by 30-240 microV over the prefeeding state in 70 cases (75%). (3) The distribution of amplitude in various groups of disease overlapped each other. The difference in amplitude or frequency would not be used as a diagnostic parameter of gastric diseases. (4) Tachygastria of 5-7.3 cycles per minute was observed in 15 of the 95 patients. The longest episode was a wave with 7.3 cycles per minute lasting for 20 minutes. It is difficult to evaluate the clinical significance of the observed tachygastria.