Abstract: The severe acute respiratory syndrome coronavirus 2 Omicron variant was emerged in November 2021 and swept the world rapidly in the following months. Countries around the world have seen a new round of outbreaks with Omicron as the main circulating strain. Omicron poses a significant threat to existing vaccines and antibody-related therapies because of its greater mutations in its spike protein and strong immune evasion. Although Omicron causes mild symptoms of the disease, its high transmission rate has significantly increased the strain on health systems around the world. This article reviewed the etiological characteristics, source of variation, transmission characteristics, epidemic status and prevention and control measures of Omicron variant in order to provide suggestions for scientific prevention and control.