Sinus lift surgery is an established and reliable technique because of the low rate of postoperative complications and the success of implants placed in the grafted area. However, as with any surgical procedure, it is not immune from risk. To minimize this risk, the surgery must be carried out by experienced professionals with appropriate planning. The major part of success with implant placement in posterior maxilla by grafting procedure lies in treatment planning. The in-depth knowledge of anatomy of the maxillary sinus is utmost important before actually performing the sinus floor elevation procedure. In this article we will be discussing in detail the various anatomical and clinical considerations in the posterior maxillae for sinus floor elevation procedure to ensure a predictable success with minimum complication. Keywords: Maxillary sinus, Anatomy, Antrum of highmore, Ostium, Schneiderian membrane.