This CME article explores the evolving role of endosonography in otorhinolaryngology and head and neck surgery. Endosonography offers significant potential to improve imaging inside the upper respiratory tract, particularly with advancements in probe technology and imaging resolution. The article will describe the sonoanatomy of the oral cavity, pharynx, and larynx and the selection of probes and scanning techniques used for the various anatomical sites. Transoral ultrasound can be used to improve the diagnosis of salivary gland diseases, oropharyngeal abscesses, and ultrasound-guided puncture and biopsy. Endoscopic endolaryngeal ultrasound is used especially for diagnosing small laryngeal cancer and determining infiltration status. The article highlights the role of endosonography in managing oncologic diseases, especially in oral tongue carcinoma, where it aids in surgical planning by assessing the depth of invasion. In cases of HPV-positive carcinoma of unknown primary, high-frequency endosonography is crucial for detecting small tumors in the oropharyngeal region. In summary, the article advocates the broader integration of endosonography in clinical practice, highlighting its potential to enhance diagnostic accuracy and improve patient outcomes in head and neck oncology.