Background: Posterior superior alveolar artery (PSAA) is the most important limiting anatomic structure while lateral approach sinus surgeries. PSAA should be taken into consideration to avoid bleeding during preparation of bony window.Purpose: The aim of this article was to inform topography of PSAA and to evaluate measurements of this vital structure.Materials and Methods: Three hundred and fifty-four cone-beam computed tomography (CBCT) images of PSAA from 177 patients were evaluated retrospectively.Localization of PSAA, diameter of PSAA, classification of PSAA diameter, distance between PSAA and crest, buccal bone thickness, palatal bone thickness, crest height, and crest width were recorded for each posterior tooth separately.Results: The mean age of 177 patients was 54.05 ± 18.33 years. Although the most frequent localization of PSAA was intraosseous in premolar region, they were below Schneiderian membrane in molars. PSAA diameter was measured frequently less than