Recently,　selective　laser　melting　(SLM)　technology　has　been　broadly　used　in　medical　application　because　it　is　suitable　for　the　fabrication　of　personalized　implants.　However,　it　is　well　accepted　that　the　parts　produced　by　SLM　with　unique　microstructure　would　affect　the　corrosion　resistance,　which　may　result　in　the　release　of　metal　ions　and　further　induce　peri-implantitis.　In　this　work,　self-developed　Ti6Al4V3Cu　gas-atomized　powders　with　antibacterial　property　were　fabricated　for　SLM　technology.　The　differing　heat　treatments　were　applied　to　SLM-produced　Ti6Al4V3Cu　alloys　to　address　the　microstructure　to　improve　the　corrosion　resistance.　The　microstructure　of　the　Ti6Al4V3Cu　alloys　with　heat　treatment　was　investigated　to　insight　into　the　relationship　between　evolved　microstructure　and　their　corrosion　behavior.　The　corrosion　behavior　of　the　Ti6Al4V3Cu　alloys　was　studied　in　terms　of　the　electrochemical　and　static　immersion　test.　The　microstructural　characterization　depicted　that　the　formation　of　the　equilibrium　structure　with　increasing　the　grain　size　and　releasing　residual　stress　was　observed　when　elevated　heat　temperature.　The　corrosion　test　suggested　that　the　Ti6Al4V3Cu　alloys　heated　at　760　°C　for　2　h　ameliorated　the　corrosion　resistance.　The　results　indicated　that　a　proper　heat　treatment　is　an　efficient　strategy　for　improving　the　corrosion　resistance　of　Ti6Al4V3Cu　alloys.　©　2021　The　Authors.