Background: Asterion is the meeting point of lower end of lambdoid suture, parietomastoid suture and the occipitomastoid suture. In infants, asterion is a site of mastoid fontanels or posterolateral fontanels. It is triangular is shape. On the basis of presence or absence of suture, asterion can be classified as type I and type II. During surgical approaches asterion should be given consideration to the superficial anatomic reference points of the posterior cranial fossa. Important reference points of asterion are of great importance in surgical procedures to locate the site where the initial trepanning will be carried out. The study of asterion morphology and morphometry may be helpful to Neuro and ENT surgeon.