From March 11, 2020 to October 31, 2020, we enrolled and studied 239 SARS-CoV-2-positive and 253 SARS-CoV-2-negative patients to determine associations of the SNPs rs2070788, rs383510, and rs12329760 in the gene TMPRSS2 with susceptibility to SARS-CoV-2 infection and severity of COVID-19. This evidence concerns the gene TMPRSS2 and COVID-19.