Purpose: The Aims and Objectives of this study were to determine the infiltration of mandibular ameloblastoma beyond the radiographic margin and the aggressiveness of any histological varieties. Patients and Methods: A total number of six patients with mandibular ameloblastoma were treated with resection of the mandible in this study. Out of six patients, four were females and the rest males. The resected mandible with at least 1cm clearance was then cut serially in the longitudinal axis with a uniform width of 1mm from the cut margin. The serial sections were decalcified, processed and microscopic examination was done to find out the infiltration. Results: The extent of infiltration in mesial and distal side from the radiographic margin was calculated. The infiltration ameloblastoma beyond the radiographic margin ranges from 0.5mm to 8mm. The average infiltration is 4.63mm. The follicular and plexiform types showed the maximum infiltration whereas the unicystic mural type showed the minimum. This study shows that the multicystic ameloblastomas of the mandible should be treated by resection of the mandible with at least 1cm linear bony margin.