Human Corona Viruses (HCoVs) are the displaying pandemic disease globally. It is commonly regarded as the pathogens of the respiratory system coupled in the midst of broad assortment of respiratory diseases. These HCoVs also revealed to possess an enveloped positive-sensed RNA viruses and multiplies mainly in the protoplasm of the host. It is been acknowledged that the virus common route of its entry is by contacting and later coalescing with the external surface of the host. Once entered the niceties of the corona virus need to be clearly understood. Although several advancements acknowledged about its structural properties as well as emphasized physicochemical and molecular mechanism of the coronavirus yet unable to distinctively comprehend on the unusual property of trimeric S protein. Characteristically the action of the coronavirus fusion peptide (FP) and induction of consensual alteration in the viral fusion proteins necessitate for comprehension. In our present review, we have imparted a concise introduction to corona viruses and discussed on their replication, physiology and molecular mechanism of pathogenicity, further portray different types of corona viruses. Hence this review noticeably highlights the mutated form of (SARS-CoV) and how it poses its threat all over world.

Keywords: SARS-CoV, COVID-19, Corona virus, Pandemic disease, Positive stranded RNA virus