Since　the　beginning　of　the　COVID-19　pandemic,　numerous　variants　of　severe　acute　respiratory　syndrome　coronavirus　2　(SARS-CoV-2)　have　emerged,　including　five　variants　of　concern　(VOC)　strains　listed　by　the　WHO:　Alpha,　Beta,　Gamma,　Delta　and　Omicron.　Extensive　studies　have　shown　that　most　of　these　VOC　strains,　especially　the　currently　dominant　variant　Omicron,　can　escape　the　host　immune　response　induced　by　existing　COVID-19　vaccines　to　different　extents,　which　poses　considerable　risk　to　the　health　of　human　beings　around　the　world.　In　the　present　study,　we　developed　a　vaccine　based　on　inactivated　SARS-CoV-2　and　an　adjuvant　consisting　of　aluminum　hydroxide　(alum)　and　CpG.　The　immunogenicity　and　safety　of　the　vaccine　were　investigated　in　rats.　The　candidate　vaccine　elicited　high　titers　of　SARS-CoV-2-spike-specific　IgG　antibody　and　neutralizing　antibody　in　immunized　rats,　which　not　only　neutralize　the　original　SARS-CoV-2,　but　also　showed　great　cross-neutralization　activity　against　the　Beta,　Delta　and　Omicron　variants.　©　2022　by　the　authors.