Copper　coatings　were　fabricated　on　stainless　steel　plates　by　cold　spraying.　Attachment　and　colonization　of　Bacillus　sp.　on　their　surfaces　in　artificial　seawater　were　characterized,　and　their　effects　on　anticorrosion　performances　of　the　coatings　were　examined.　Attached　bacteria　were　observed　using　field　emission　scanning　electron　microscopy.　Electrochemical　behaviors　including　potentiodynamic　polarization　and　electrochemical　impedance　spectroscopy　with/without　bacterial　attachment　were　evaluated　using　commercial　electrochemical　analysis　station　Modulab.　Results　show　that　Bacillus　sp.　opt　to　settle　on　low-lying　spots　of　the　coating　surfaces　in　early　stage,　followed　by　recruitment　and　attachment　of　extracellular　polymeric　substances　(EPS)　secreted　through　metabolism　of　Bacillus　sp.　The　bacteria　survive　with　the　protection　of　EPS.　An　attachment　model　is　proposed　to　illustrate　the　bacterial　behaviors　on　the　surfaces　of　the　coatings.　Electrochemical　data　show　that　current　density　under　Bacillus　sp.　environment　decreases　compared　to　that　without　the　bacteria.　Charge-transfer　resistance　increases　markedly　in　bacteria-containing　seawater,　suggesting　that　corrosion　resistance　increases　and　corrosion　rate　decreases.　The　influencing　mechanism　of　bacteria　settlement　on　corrosion　resistance　of　the　cold-sprayed　copper　coatings　was　discussed　and　elucidated.