Since the outbreak of coronavirus disease 2019 (COVID-19), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has generated more than 10 000 variants. Some of them deserve our concern because it may become more infectious, or show increased pathogenicity with higher mortality, or it is no longer detectable with current assays, or it may evade immune protection conferred by available vaccines. On May 31, World Health Organization (WHO) proposed a new system to name SARS-CoV-2 variants. In this review, four worldwide spread SARS-CoV-2 variants were discussed comprehensively, including the India variant that is responsible for recent endemic of COVID-19 in Guangzhou.