Introduction: Implant dentistry had widened the prosthetic possibilities; therefore they became commonly used in many ways for substitution of lost teeth. However, there may be contraindications for the placement of dental implants. presence of sinus pneumatization in the posterior maxilla is a frequent anatomical obstacle; occurs as a result of gradual thinning of sinus walls with aging and reduction of maxillary masticatory forces. preparation of buccal window to gain access to the sinus cavity followed by elevation of the Schniederian membrane to create secluded compartment for augmentation material and /or implant placement. PRF can be used as a sole filling material during a simultaneous sinus lift and implantation stabilized a high volume of natural regenerated bone in the subsinus cavity up to the tip of the implants; and considered a satisfactory alternative.   Materials and methods: Twenty medically free patients (both males and females) received sinus floor augmentation with simultaneous implant placement. The patients were divided into two groups; where first group received platelet rich fibrin (PRF) as filling material with PRF membrane; while the other group received xenograft  with collagen membrane.   Results: When comparing the L-PRF group with xenograft group after 5 months, it was found that mean crestal bone loss in L-PRF group was less than that in xenograft group. Conclusion: L-PRF can be used successively as a sinus grafting material and as a membrane.