Introduction There is a noticeable increase in the incidence of acute invasive fungal sinusitis which coincides with the ongoing coronavirus pandemic. It is a potentially-lethal fungal infection, with the most common form being the rhino-orbito-cerebral presentation. Objectives The aim of the present study is to discuss the different epidemiological factors, risk factors, clinical presentations and outcomes of acute invasive fungal sinusitis which is noticeably related to the coronavirus disease 2019 (Covid-19) pandemic. Methods The present cross-sectional cohort study included 22 adult patients who presented with Covid-19-related acute invasive fungal sinusitis. The diagnosis of acute invasive fungal sinusitis was confirmed by histopathological biopsy. All data, including demographics, risk factors, clinical findings, different lines of treatment and their outcomes, were recorded and analyzed. Results All patients had diabetes mellitus (100%), and 17 (77.3%) had been submitted to systemic steroids. All patients (100%) had unilateral sinonasal disease. Proptosis was found in 15 patients (68.2%), ophthalmoplegia was observed in 12 patients (54.5%), and intracranial affection occurred in 10 patients (45.5%). A total of 20 patients (90.9%) received liposomal amphotericin B. Surgical debridement was performed in 18 patients (45.5%). Non-septated mycelia was present in 19 biopsies (86.4%), while 3 (13.6%)showed septated mycelia. Total improvement was achieved in 10 patients (45.5%), while the mortality rate was of 27.3% (6 out of 22 participants). Conclusion Diabetes mellitus is the most common preexisting medical condition associated with Covid-19-related acute invasive fungal sinusitis. Systemic corticosteroid therapy is considered a predisposing factor. It is necessary to raise the level of awareness to diagnose this condition, especially in patients with Covid-19 infection or those who have recently recovered from it.