The management of the clinically N0 neck in patients with head and neck cancers still remains controversial. Elective neck dissection is traditionally recommended when the subside of the head and neck, such as the oral cavity and supraglottic area, confers at least a 15-20% risk of lymphatic spread. However, elective neck dissection may cause an increase in patient morbidity and mortality rates. The emergence of sentinel lymph biopsy provides the possibility of accurate pathological staging of the cervical node with a less invasive procedure. The present review will summarize the role of sentinel lymph node biopsy and its application areas when evaluating occult metastases in patients with head and neck cancers.