The pharyngoesophageal diverticulum in the lower part of the neck can be detected using neck ultrasonography. We present a case of pharyngoesophageal diverticulum mimicking a thyroid nodule, which was found incidentally by ultrasonography, and discuss its peculiar findings, which might be useful to diagnose pharyngoesophageal diverticulum and to prevent invasive procedures such as needle aspiration biopsy.