© 2019, Japanese Society of Anesthesiologists. There is little evidence of gastric excretion after ingestion of solids. We examined gastric emptying times after ingesting normal breakfast in healthy adult volunteer using ultrasonography. Eight adult volunteers fasted for 8 h, and we examined the gastric antral area in the right lateral decubitus position using ultrasonography. Sixteen adult volunteers ingested normal breakfast. We evaluated the gastric antral area in the same manner at two consecutive time points before lunch. Gastric volume was calculated by using an approximation formula based on the antral area. Correlation coefficients between gastric volume and fasting time were calculated. The calculated gastric volume from the gastric antral area after 8 h fasting was 53.1 ml. The gastric volume correlated significantly with fasting time (r = − 0.811, P < 0.001). The time when the attenuation line obtained from two measurements between breakfast to lunch in each subject overlapped the fasting stomach volume (53.1 ml) was taken as gastric empty time. The calculated gastric emptying time was 276.4 ± 58.9 min. This result shows that gastric emptying time was lower than 5 h average after a typical breakfast that contains various food in healthy adult volunteers. However, further research is necessary to establish the clinical safety implications of these findings.