Pseudoalteromonas　sp.　CuT4-3,　a　copper　resistant　bacterium,　was　isolated　from　deep-sea　hydrothermal　sulfides　on　the　Southwest　Indian　Ridge　(SWIR),　is　an　aerobic,　mesophilic　and　rod-shaped　bacterium　belonging　to　the　family　Pseudoalteromonadaceae　(class　Gammaproteobacteria,　order　Alteromonadales).　In　this　study,　we　present　the　complete　genome　sequence　of　strain　CuT4-3,　which　consists　of　a　single　circular　chromosome　comprising　3,660,538　nucleotides　with　41.05%　G　+　C　content　and　two　circular　plasmids　comprising　792,064　nucleotides　with　40.36%　G　+　C　content　and　65,436　nucleotides　with　41.50%　G　+　C　content.　In　total,　4078　protein　coding　genes,　105　tRNA　genes,　and　25　rRNA　genes　were　obtained.　Genomic　analysis　of　strain　CuT4-3　identified　numerous　genes　related　to　heavy　metal　resistance　(especially　copper)　and　EPS　production.　The　genome　of　strain　CuT4-3　will　be　helpful　for　further　understanding　of　its　adaptive　strategies,　particularly　its　ability　to　resist　heavy　metal,　in　the　deep-sea　hydrothermal　vent　environment.