Killian-Jamieson diverticulum (KJD) is a rare esophageal diverticulum that protrudes through the muscular gap in the anterolateral wall of the proximal cervical esophagus inferior to the cricopharyngeus. Although several patients with bilateral KJD have been reported, high-resolution ultrasound (US) image of bilateral KJD has never been reported. A 71-year-old man visited our hospital for annual follow-up of known thyroid nodules. In addition to the previously noted thyroid nodules, two arc-shaped hyperechoic lesions with reverberation artifacts, which suggested air-containing lesions, were unexpectedly seen posterior to bilateral thyroid lobes. Although the connection between the esophagus and the lesions was not definitely visible on US, our first differential diagnosis was esophageal diverticula. They were confirmed to be bilateral KJD on the following pharyngoesophagography. If US features are not enough to differentiate esophageal diverticulum from suspicious thyroid nodule, pharyngoesophagography can be performed instead of invasive fine-needle aspiration to obtain a definite diagnosis of incidentally detected esophageal diverticulum.