Different forms of allogenous and autogenous bone grafts have been studied for their potential use as bone substitutes. Although autogenous bone grafts is a treatment alternative for bone regeneration and repair they have several disadvantages like limitation of graft volume available, donor site morbidity and is technique sensitive. Thus, use of other materials like processed bovine dentine and Bone Xenograft (Bio-Oss) presents an alternative and a relatively simple technique for bone regeneration and repair. The main aim of this study was to determine the role of Processed Bovine Dentine and Bone Xenograft (Bio-Oss) in bone regeneration and repair and to compare these two groups histlogically. A total of ten healthy adult Albino male rats, aged 4 weeks weighing between 150 – 200gms were used in the study. Three round surgical defects of approximately 1mm in diameter were drilled in both the right and left femur. Processed bovine dentine was placed in the right femur and Bio-Oss was placed in the left femur. Group I: - Processed Bovine Dentine.Group II: - Bone Xenograft (Bio-Oss). Bio-Oss graft displayed osteoconductive properties and the best bone formation with complete resorption and organization of the grafted materials. Based on histological findings, though Processed Bovine dentine displayed osteoconductive properties its effect on bone formation was slower compared to that of Bio-Oss. The results of the present study supports that the use of Processed Bovine Dentine seems to be an alternative bone substitute, although less effective than Bone Xenograft (Bio-Oss).