Background: Guided bone regeneration has been tried using a variety of barrier membranes, and it is thought to be achieved when osteoprogenitor cells are allowed to repopulate the area of the bone defect solely while non-osteogenic tissues are prevented from entering. PRF, have the advantage that without anticoagulants, a fibrin matrix that incorporates the full set of growth factors trapped within its matrix can slowly release these growth factors over time. Furthermore, L-PRF contains white blood cells, which are key contributors to wound healing. The aim of this study was to evaluate the benefits of using L-PRF in bone regeneration when utilizing GBR technique. Methods: The study involved six mature mongrel dogs, each weighing at least 18 kg. In the first phase, four standardized saddle-type defects were prepared. After a two-month recuperation period, a xenogeneic block graft was utilized in the two groups. In group (1), block graft was covered by a collagen membrane (Block + C M), while in group (2), two L-PRF membranes were added first before top coverage by collagen membrane (Block + L PRF + C M). Animals were subjected to surgical reentry after a three-month healing period following grafting for clinical observation and then euthanized for histological processing. Results: In group 1, there was a statistically significant difference between (New bone apical side) and each of (New bone periosteum side) and (New bone intermediate) (p≤0.001). In group 2 no statistically significant difference between (New bone periosteum side), (New Bone intermediate) and (New Bone apical side) (p=0.225). Conclusion: With the inherent limitations of this study, the usage of the (L PRF) in ridge augmentation appears to enhance the quality of regenerated bone