Paralysis of the mental nerve is one of the principal complications of surgery of the mandibular canal and mental foramen region. Therefore, identification of mental foramen is important for dental surgeons in nerve block and surgical procedures like apico curettage of mandibular premolars, amalgam filling, peridental surgery etc. to avoid injury to neurovascular bundle. Accessory mental foramina tend to exist in the apical area of the first molar and posterior or inferior area of the mental foramen. The accessory branches of the mandibular canal showed common characteristics in the course of gently sloping posterosuperior direction in the buccal surface area. Verification of the existence of accessory mental foramina would prevent accessory nerve injury during periapical surgery. In root canal treatment, the possibility of accessory mental foramina-related nerve paresthesia seems low unless the mental foramen and mandibular canal are injured. Therefore, prior surgical knowledge of morphology and morphometry of mental and accessory mental foramen peculiar to particular block may enable effective mental block anaesthesia. Besides this, as mental foramen and accessory mental foramen have been found to vary in position in different ethnic groups. So, it is important to study the morphology and morphometry of mental foramen and accessory mental foramen. Hence this study was carried out. Present study was conducted using dried adult human mandibles of both sexes. Size and position were determined using digital vernier callipers. Incidences and shapes of mental foramen and accessory mental foramen were also observed. Mental foramen was present in all one hundred observed mandibles and it is bilateral. Accessory mental foramen was present in 8 percent on left side while on right side, it was 5 percent. None of the mandibles presented with bilateral accessory mental foramen. Shape was predominantly round with 94 percent on right side and 87 percent on left side while it was oval in 6 percent on right side and 13 percent on left side. Average size of mental foramen was 2.79 mm on right side while it was 2.57 mm on left side. Average size of accessory mental foramen was 1.00 mm varying from 0.5 mm to 4.00 mm. Mental foramen was located below the apex of second premolar in 68.8 percent mandibles while it is 17.8 percent between first and second premolars and in 11.5 percent, it is between second premolar and first molar. Accessory mental foramen lies 0.67 mm lateral to mental foramen and below the apex of first molar tooth.