The lingula of the mandible is a small-tongue-shaped bone projection overlaying the mandibular foramen, and it is clinically significant in oral and maxillofacial surgical procedures. This study aims to analyze the shapes of the lingula and its relationship with the surface of the mandibular ramus, and to record data about the population in Southern Brazil. The maxillofacial study of the lingula in 80 dry mandibles in adult individuals was conducted. The lingula of the two rami of each mandible were assessed and classified in the following shapes: triangular, truncated, nodular and assimilated. The triangular shape was analyzed according to its direction in relation to the condyle or the posterior region of the mandible posterior ramus, and also according to its relationship with the inner surface of the mandibular ramus: assimilated, free or partially free. The occurrence of accessory mandibular foramens in each mandibular ramus was also recorded. The triangular shape of the lingula was found in 66 sides (41.3%), seeing that in 21 mandibles (42 sides) it was noticed both on the right side and the left side, whereas 13 occurred on the right side and 11 on the left side, unilaterally. The truncated lingula was present on 58 sides (36.3%), and the nodular lingula was noticed on 17 sides (10.5%); as to the assimilated lingula it was found on 19 sides (11.9%). Accessory foramens were found in 11.3 and 3.8% of the right and left mandibular rami, respectively. Considering that the lingula shows morphological variants in different populations, these results include significant data of the population in the South of Brazil regarding the morphometric study of the mandible, also playing a role to avoid failure of the anesthetic surgical block of the inferior alveolar nerve.