OBJECTIVE Although distal gastrectomy followed by Billroth-I reconstruction has been a standard surgical procedure for over 100 years, gastric emptying of liquid and solids after this procedure remains poorly understood, despite its contribution to postgastrectomy complications such as dumping syndrome and reflux esophagitis. A simple way to standardize measurement and generate normal values is needed. This study proposed a new, accurate and easy method, "dual phase method", for gastric emptying after distal gastrectomy. METHODS Liquid- and solid-phase gastric emptying were measured using a combined test consisting of acetaminophen and sulfamethizole capsule ingestion, respectively. Data from 12 patients (B-I group) who had undergone distal gastrectomy with D2 lymph node dissection and truncal vagotomy followed by Billroth-I reconstruction were compared with those from 14 healthy volunteers (control group). RESULTS A two-factor repeated measures ANOVA (analysis of variance) demonstrated a highly significant difference in the sequential changes in the serum acetaminophen concentration after ingestion between the two groups (p<0.0001). On the other hand, the sequential changes in the serum sulfamethizole concentration after ingestion was similar in the two groups (p=0.91). CONCLUSIONS Gastric emptying of liquids is rapid after distal gastrectomy followed by Billroth-I reconstruction. However, emptying of solids is unchanged. The data obtained in this study can be a point of reference for comparing gastric emptying following gastrectomy.