The objective of this comparative study was to correlate the effect of previous infection with human coronavirus (HCOV) on the incidence of Schneiderian membrane perforation (SMP) and postoperative complications of maxillary sinus augmentation. Patients and methods: Twenty-four eligible patients with atrophic posterior pneumatized maxilla (assessed radiographically) were enrolled to the current study to undergo sinus floor augmentation. The patients were divided into two equal groups; positive history of COVID 19 infection/ study group and negative history of COVID-19 infection/control group. All patients were imaged by cone beam computed tomography (CBCT) three times; before surgery (for inclusion), immediately after surgery (1 week), and at the end of follow-up (4 months). Clinical and radiographic assessment were performed to monitor the incidence of SMP and Postoperative complications. Results: The mean patient's age was 48.75±6.69 & 52.42±5.82 for the study and the control group respectively. There was no statistically significant difference (p=0.059) regarding SMP among the studied groups. Regarding the post-operative complications, the incidence of facial pressure was significantly higher in the study group than the control group (p=0.035). However, there was no significant difference among groups in terms of the other postoperative complications. Conclusion: COVID-19 induced sinusitis could be a potential risk factor for postoperative complications of sinus augmentation surgery.