Azo　dye-containing　sewage　is　commonly　detected　at　high　salinity,　temperature　and　pH.　In　this　study,　a　halo-thermoalkalophilic　azo　dye　decolorization　consortium　was　enriched　and　named　“consortium　HL”.　Consortium　HL　which　was　dominated　by　Marinobacter　(84.30%),　Desulfocurvibacter　(1.89%),　and　Pseudomonas　(1.85%),　was　able　to　completely　decolorize　Direct　Blue　5B　(DB5)　during　incubation　with　the　material　at　5%　salinity,　50　°C,　and　pH　9　for　30　h.　The　decolorization　mechanism　was　proposed　based　on　combined　metagenomic　analysis,　GC‒MS,　and　enzymatic　activity　detection.　The　action　of　the　consortium　HL　showed　great　tolerance　to　variations　in　salinity,　temperature　and　pH.　A　phytotoxicity　study　indicated　that　the　metabolic　intermediates　showed　no　significant　toxicity　to　the　generation　of　Cucumis　sativus　and　Oryza　sativa　seeds.　This　study,　in　which　azo　dye　decolorization　and　degradation　under　high-salt,　high-temperature　and　high-alkalinity　conditions　were　investigated　and　deeply　analyzed　by　metagenomic　information,　is　the　first　report　regarding　the　ability　of　Marinobacter　to　decolorize　azo　dyes　at　high　temperatures.　©　2024　Elsevier　Ltd