Objective: The aim of this study was to investigate the effect of ubiquinone and/or calcium carbonate (CaCO3) on bone mineral density in rabbits at healing site in mandibular bone postoperatively. Materials and Methods: Sixty healthy white male New Zealand rabbits almost the same age, weight and circumstance were used in this study. All animals were submitted to operation in the mandibular bone region. The groove of 2mm diameter and 6mm length was drilled by the heavy-duty dental engine. After operation rabbits were randomly divided into six groups (each group 10 rabbits) five rabbits for each period; control group (groove was not filled by anything) and treated groups which subdivided into five groups as follows: group I (groove was filled with Ubiquinone), group II (groove was filled with CaCO3), group III (groove was filled with CaCO3: Ubiquinone as a ratio (1:1)), group IV (groove was filled with CaCO3: Ubiquinone as a ratio (1:2)) and group V (groove was filled with CaCO3: Ubiquinone as a ratio (2:1)). Estimated BMD using Densitometry analysis was measured after 15 and 30 days respectively. Results: Statistical analysis showed significant differences between all groups (control and treated). The estimated BMD showed significant increase group I(101±1.05), group II(111±2.23), group III(125±3.54), group IV(126±5.13) and group V(133±6.29) comparing to control group (92±0.15) at follow-up times at 15 day. Also in the present study we found that significant decrease in BMD after 30 days of operation in group I(144±3.45), group II(153±6.24), group III(160±8.94), group IV(165±9.11) and group V(182±12.56) compare to control group(109±1.25) respectively. Adding the ubiquinone and/or CaCO3 showed a significant increase in BMD manifested by bone healing like space-filling and newly formed bone trabeculae and a high number of lacunas compared with the control group. Conclusion: This study concluded that the addition of ubiquinone and/or CaCO3 was successfully increasing in bone healing by increasing BMD compared with the control group. Keywords: Ubiquinone, CaCO3, Bone healing, BMD (Bone Mineral Density).