Aim: To evaluate effect of bilateral balanced & monoplane occlusion of implant retained mandibular overdenture on biting force and masticatory efficiency. Subjects and Methods: Six completely edentulous patients were selected for this study; all patients were received conventional upper and lower dentures that include bilateral balanced articulation for three months. Then each patient will receive two root form implant in the interforaminal region. The dentures processed to retrofit onto the implant. After adjustment and adaptation period occlusal biting force was recorded bilaterally at the canine and first molar area; although masticatory efficiency were evaluated by assessing chewing time and number of chewing strokes with different type of foods. Results: Significant increase in the maximum biting force and masticatory efficiency with mandibular overdentures. Conclusion: biting force and masticatory efficiency were improved with implant retained mandibular overdentures; in addition to prefer the bilateral balanced occlusion in case of biting force as it provides maximum biting force and better masticatory efficiency.