To evaluate the effect of periosteum preservation approach in endoscopic sinus surgery on subantral bone augmentation in patients with the maxillary sinus pathology. The results of subantral bone augmentation of 245 patients who underwent surgery for the paranasal sinus pathology (chronic rhinosinusitis, fungus ball and maxillary sinus cysts) were studied. In 146 patients endoscopic sinus surgery was performed with periosteum preservation approach (main group), and 99 patients underwent traditional surgery (control group). The total proportion of patients who had the perforation of the Schneiderian membrane during subantral augmentation in the group with endoscopic sinus surgery according to the traditional method was 21.21%, which is significantly higher than in patients who underwent surgery in accordance with the periosteum preservation principles – 9.59% (p<0.05). The frequency of application of periosteum restore technologies in subantral augmentation was significantly higher in the control group (49.49%) compared with the main group (24.66%) (p<0.05). The frequency of other complications after subantral augmentation in patients who underwent surgery according to the traditional method was 20.59%, which is significantly higher than in patients with periosteum preserving principles – 10.27% (P<0.05). A reduction in the frequency of complications in subantral bone augmentation, provided that the principles of periosteal preservation in sinus surgery are observed, can be associated with low traumatization of the periosteum, and therefore the preservation of its elastic features with the avoidance of tight adhesions between the periosteum in the area of elevation and the underlying bone.