OBJECTIVE Eustachian tube dysfunction is a common problem and transnasal endoscopic balloon dilation of the Eustachian tube (ET) is a new surgical technique. The goal of this study is to review the evolution of this novel technique and study the preliminary outcomes. METHODS Balloon catheter dilation of the 100 Eustachian tubes in 70 adults was performed at a tertiary medical center from January 2009 to January 2011. A 5-mm sinus balloon catheter was endoscopically placed transnasally into the proximal ET to dilate the cartilaginous ET. Cases were reviewed with respect to indications, outcomes, and complications. RESULTS Of the 100 ETs, ear fullness and pressure were improved in 71% of patients studied for 26.3 weeks (± 3.6). Of 8 patients followed for a minimum of 34 months, 87% reported persistent improvement. One complication is reported. CONCLUSIONS Endoscopic transnasal ET balloon dilation is a novel approach to treating ET dysfunction. Benefits can be durable up to 3 years. This technique holds much promise and merits further investigation.