The demerit of pylorus-preserving gastrectomy(PPG)is the postprandial abdominal fullness(PAF)with gastric stasis in the remnant stomach(GSRS). We investigated the relationship between clinical findings and GSRS, and between GSRS and interdigestive migrating motor complex(IMMC)in PPG patients. A total of 30 patients(17 men and 13 women, mean age of 62.3 years)after PPG for early gastric cancer(Billroth Ⅰ)were divided into 2 groups(group A; 18 patients with GSRS, group B; 12 patients without GSRS). The relationship between GSRS including clinical findings and IMMC was studied from 1.5 to 3 years after operation. A catheter equipped with a micro-tip force transducer was inserted transnassally into the remnant stomach and duodenum in a supine position, and the IMMC was studied. All patients were Stage ⅠA(mucosal cancer, no lymph node metastasis, no distant metastasis). The remnant stomach was 1/3 compared with stomach size before operation. The length of the antral cuff in group A(1.5±0.2 cm)was significantly shorter than group B(3.2±0.3 cm)(p =0.0004). Appetite was significantly recognized in group B compared with group A(p=0.0067). PAF was significantly recognized in group A compared with group B(p=0.0001). Reflux esophagitis was found in group A more than group B. Early dumping syndroms did not found significant differences in both groups. In endoscopic esophagogastric finding of the remnant stomch, gastritis with GSRS was significantly found in group A compared with group B(p=0.0001). The IMMC was significantly recognized in group B compared with group A(p<0.0001). The occurrence of the PAF due to the GSRS may be caused by abscens of the IMMC.