Background The introducer method of percutaneous endoscopic gastrostomy (PEG) minimizes procedure-related peristomal infection. Ultrathin transnasal endoscopy (UTE) allows comfortable endoscopic examination of patients with fewer adverse effects and passage of the endoscope through a narrow esophagus or oropharynx. This study aimed to investigate the clinical outcomes for the introducer method of PEG with UTE. Methods Patients who underwent the introducer method of PEG with UTE between March 2009 and May 2012 were analyzed. The outcomes and complications of the patients within 180 days after gastrostomy placement were investigated. Result During the study period, 92 patients (31.9 % male; age, 67.7 +/- 16.6 years) underwent the introducer method of PEG with UTE. The major indications for PEG insertion were stroke (40.4 %), esophageal cancer or head and neck cancer (27.1 %), and neurologic disorder (14.9 %). Esophageal stenosis was identified by endoscopy or imaging in 14 patients before PEG. In all the patients, UTE was successfully introduced through the nasal cavity. In 90 (97.8 %) of the 92 patients, PEG was successfully inserted. Insertion of the endoscope into the stomach was impossible in two patients because head and neck cancer caused severe narrowing of the upper esophagus. No procedure-related peristomal infection, gastric contents leakage, or bleeding occurred within 30 days after gastrostomy placement. In eight patients (8.7 %), catheter displacement occurred within 30 days. Catheter displacement in 44 patients (47.8 %) and gastric contents leakage in eight patients (9 %) occurred within 30-180 days after gastrostomy placement. Conclusion Introducer PEG with UTE is a useful method for gastrostomy placement with a high success rate. This technique allows procedure-related complications to be avoided and permits the use of endoscopy in patients with narrow esophagi or oropharynges. However, the long-term durability of the balloon-type catheter is questionable.