Siriraj Hospital began the service for patients with eye, ear, nose, and throat diseases first time in 1930 as parts of Surgery Department. At that time, there were only 2 staff physicians; Dr. Dang Kanchanarunya and Dr. Noble. In 1936, the EENT training began and Dr. Porn Varavech was the first resident. In 1945, the department of Eye-Ear-Nose-and Throat (EENT) was officially separated from the department of Surgery. The services of EENT department at that time were dominantly treatment and operation of ear diseases especially on otitis media.

The Department of Otorhinolaryngology, Faculty of Medicine Siriraj Hospital was officially set up In 1970 and Professor Porn Varavech who was the first chairman of the department had developed substantial advancement in the field, for examples; Laryngo – Broncho – Esophagology, Radical mastoidectomy (chisel), Otogenic brain abscess, Sinus surgery (chisel), Tonsillectomy (dissection), and Tracheostomy, etc.

In 1972, Associate Professor Dr. Chern Saekararit, the first physician in Thailand and Asia came who was certified by the American Board of Otolaryngology (Tulane University, USA since 1962) was appointed the chairman of the department. Since then, numerous progresses in the field were recognized, for examples; Juvenile nasopharyngeal angiofibroma, Maxillectomy, Laryngectomy, Vein graft tympanoplasty, etc.
At a later time, several divisions and units have been established as follows

1972 Hearing and Speech therapy unit
1973 Neuro-Otology unit
1973 Allergy unit
1982 Laryngology Clinic
1982 Facial Plastic Surgery unit
1985 Bangkok Neuro-Otology and Hearing center
1989 Voice Clinic
1990 Inner Ear and Skull Base Surgery
1991 Middle Ear Surgery
1992 Rhinology unit
1994 Pediatric Otolaryngology
2008 Snoring clinic
2010 Swallowing unit
2011 Sleep Medicine unit