Rhizopus oryzae, also known as Rhizopus arrhizus, is a filamentous fungus that is the most common cause of mucormycosis, also referred to as zygomycosis. It is commonly found in dead organic matter. In my opinion, this microorganism is important because it is not only an opportunistic pathogen that cause human disease in immunocompromised people, such as those with diabetes mellitus, cancer, or AIDS, but also used as the source of making fermented foods and alcoholic beverages in Asia. So, this microbe is very closely connected to human life.