The COVID-19, Coronavirus Disease 2019, emerged as a hazardous disease that led to many causalities across the world . Early detection of COVID-19 in patients and proper treatment along with awareness can help to contain COVID-19 . Proposed Fuzzy Cloud-Based (FCB) COVID-19 Diagnosis Assistant aims to identify the patients as confirmed, suspects, or suspicious of COVID-19 . It categorized the patients into four categories as mild, moderate, severe, or critical . As patients register themselves online on the FCB COVID-19 DA in real-time, it creates the database for the same . This database helps to improve diagnostic accuracy as it contains the latest updates from real-world cases data . A team of doctors, experts, consultants are integrated with the FCB COVID-19 DA for better consultation and prevention . The ultimate aim of this proposed theory of FCB COVID-19 DA is to take control of COVID-19 pandemic and de-accelerate its rate of transmission among the society.