Most　regions　of　the　Antarctic　continent　are　experiencing　increased　dryness　due　to　global　climate　change.　Mosses　and　lichens　are　the　dominant　vegetation　of　the　ice-free　areas　of　Antarctica.　However,　the　molecular　mechanisms　of　these　Antarctic　plants　adapting　to　drought　stress　are　less　documented.　Here,　transcriptome　and　metabolome　analyses　were　employed　to　reveal　the　responses　of　an　Antarctic　moss　(Pohlia　nutans　subsp.　LIU)　to　drought　stress.　We　found　that　drought　stress　made　the　gametophytes　turn　yellow　and　curled,　and　enhanced　the　contents　of　malondialdehyde　and　proline,　and　the　activities　of　antioxidant　enzymes.　Totally,　2,451　differentially　expressed　genes　(DEGs)　were　uncovered　under　drought　treatment.　The　representative　DEGs　are　mainly　involved　in　ROS-scavenging　and　detoxification,　flavonoid　metabolism　pathway,　plant　hormone　signaling　pathway,　lipids　metabolism　pathway,　transcription　factors　and　signal-related　genes.　Meanwhile,　a　total　of　354　differentially　changed　metabolites　(DCMs)　were　detected　in　the　metabolome　analysis.　Flavonoids　and　lipids　were　the　most　abundant　metabolites　and　they　accounted　for　41.53%　of　the　significantly　changed　metabolites.　In　addition,　integrated　transcriptome　and　metabolome　analyses　revealed　co-expression　patterns　of　flavonoid　and　long-chain　fatty　acid　biosynthesis　genes　and　their　metabolites.　Finally,　qPCR　analysis　demonstrated　that　the　expression　levels　of　stress-related　genes　were　significantly　increased.　These　genes　included　those　involved　in　ABA　signaling　pathway　(NCED3,　PP2C,　PYL,　and　SnAK2),　jasmonate　signaling　pathway　(AOC,　AOS,　JAZ,　and　OPR),　flavonoid　pathway　(CHS,　F3’,5’H,　F3H,　FLS,　FNS,　and　UFGT),　antioxidant　and　detoxifying　functions　(POD,　GSH-Px,　Prx　and　DTX),　and　transcription　factors　(ERF　and　DREB).　In　summary,　we　speculated　that　P.　nutans　were　highly　dependent　on　ABA　and　jasmonate　signaling　pathways,　ROS　scavenging,　flavonoids　and　fatty　acid　metabolism　in　response　to　drought　stress.　These　findings　present　an　important　knowledge　for　assessing　the　impact　of　coastal　climate　change　on　Antarctic　basal　plants.　Copyright　©　2022　Fang,　Li,　Zhang,　Liu,　Cong　and　Liu.