The aim of this study was to assess the prevalence, location, diameter, and distance of the posterior superior alveolar artery (PSAA) from the alveolar crest; and its association with sex, age, and dental status using cone beam computed tomography (CBCT). Retrospectively reviewed CBCT images of maxillary sinuses from 370 sinuses in 185 patients at the Faculty of Dentistry, Chulalongkorn University were evaluated. The prevalence, location, diameter, and the distance between the alveolar crest and PSAA were evaluated. The prevalence, location, diameter, and distance from the alveolar crest were compared according to sex, age, and dental status. The result revealed that the PSAA was detected in 32.16 % of sinuses and most (52.85 %) had an intraosseous location. The diameter was mostly <1 mm (80.31 %). Males had a significantly larger diameter than females (p < 0.05). Most PSAAs (65.28 %) were >15 mm from the alveolar crest. The distance from the alveolar crest was highest at the first premolar and lowest at the first molar. Most detectable PSAAs were <1 mm in diameter and ≥15 mm from the alveolar crest, indicating a low chance of severe bleeding during sinus augmentation. However, a preoperative CBCT is necessary to avoid complications and design an accurate treatment plan.