Objective: The aim of this study was to evaluate Highmore antrum sexual dimorphism by cone-beam computed tomography (CBCT) in a Peruvian population. Materials and Methods: This was a retrospective analytical study. The sample consisted of 190 CBCT scans. Inter-observer concordance was performed previously obtaining an intraclass correlation coefficient (ICC) of 0.99 for the width, length, and height of the right and left maxillary sinus. Then the dimensions of the maxillary sinus (left and right) were measured. All statistical analyses were performed using the Student's t test and Lambda de Wilks, establishing a level of significance of P 0.05. Results: It was observed that on the right side of the maxillary sinus there were only statistically significant differences between the width, height, area, perimeter, and volume of the Highmore's antrum and sex with a P 0.05. Statistically significant differences were observed between sex and the width, height, area, perimeter, and volume of the Highmore's antrum in the right side of the maxillary sinus (P 0.05), whereas the left side only showed statistically significant differences between the height and volume of the Highmore's antrum and sex (P 0.05). Conclusion: The maxillary sinuses have significant sexual dimorphism, with the parameter of height showing the greatest dimorphism according to the discriminant analysis.