Background: Mucormycosis, a rare, but severe angio-invasive disease that can have a catastrophic or fatal outcome. It is an opportunistic infection that has been mostly reported in immunocompromized and diabetic patients, and it commonly begins by invading the respiratory tract. The aim of this paper is to document the emergence of mucormycosis as a dangerous complication of covid-19 in Iraq and many countries in the world. Materials and methods: On the first of June, 1,201,352 cases of covid-19 were reported by the Iraqi Ministry of Health, and 16375 patients died because of the disease. During, the first week of June, 2021, the death of Iraqi three patients having covid-19 disease complicated by mucormycosis was reported. At least 140 patients with covid-19 disease complicated by mucormycosis have been reported throughout the world including 100 patients from India, 18 patients from Iran, 11 patients from Turkey, 7 patients from the United States of America, 6 patients from Egypt, 2 patients from Spain, and one patient from each of the following countries, Brazil, Italy, Austria, France, Mexico, UK, and the United Kingdom. Most patients were males and the disease was documented in sixteen females. Results: Sino/rhino-orbital mucormycosis with or without cerebral involvement was the most commonly reported type including 87 patients. Pulmonary mucormycosis was the second most common type, and was reported in five patients. Catastrophic outcome occurred in nineteen patients including patients ending with orbital exenteration in patients (14), and patients developed irreversible loss of vision (5). Forty patients with covid-19 with mucormycosis died including, 15 patients from India, eight patients from Iran, seven from Turkey, four deaths from USA, two deaths from Egypt, on death from Brazil, one death from Austria, one death from Mexico, and one death from the United Kingdom. Conclusions: Mucormycosis is a rare disease that is generally associated with diagnostic difficulty and delay, high morbidity, catastrophic outcome, and mortality. Diabetes mellitus and use of corticosteroids increase the risk of the development of invasive mucormycosis which may appear during the course of the covid-19, or appear as a later complication. Hyperglycemia induced impaired chemotaxis and phagocytosis of neutrophils, steroid-induced immunosuppression, and covid-19 induced immune dysregulation associated with decreased numbers of T lymphocytes, CD8+T, and CD4+T cells were considered the important factors that led to the emergence of invasive mucormycosis as a catastrophic and fatal complication of covid-19 disease. Mucormycosis can be rapidly progressive, requiring immediate surgical and medical interventions. High index of suspicion can contribute to making an early diagnosis, and providing early aggressive management which can improve survival. Upon suspicion of mucormycosis appropriate imaging is advised to determine extent of disease. First-line treatment is generally including the use of a high-dose liposomal amphotericin B. Other antifungal drugs that have been used include isavuconazole and posaconazole.