This study compares the cavitation erosion (CE) and corrosion behavior of as-cast and laser powder bed fusion (LPBF) TC4 alloys in 0.6 mol/L NaCl solution. The LPBF TC4 alloy exhibited a rectangular checkerboard-like microstructure with a more refined grain size compared to the as-cast TC4. The LPBF TC4 showed significantly better CE resistance, with approximately 2.25 times lower cumulative mass loss after 8 hours of CE. The corrosion potential of both alloys decreased rapidly at the beginning of CE, but with prolonged CE time, a consistent negative shift in corrosion potential was observed, indicating a gradual decline in repassivation ability. The initial increase in corrosion potential during early CE stages was attributed to accelerated oxygen transfer. As CE progressed, the significant decrease in corrosion potential for both alloys was due to the breakdown of the passive film. The refined and uniform microstructure of LPBF TC4 effectively suppressed crack formation and propagation, highlighting the potential of LPBF technology in enhancing the CE resistance of titanium alloys. The study provides important insights into developing high-quality, reliable, and sustainable CE-resistant materials via LPBF technology. The results indicate that LPBF TC4 has superior CE resistance compared to as-cast TC4, with a more stable passive film and better corrosion resistance. The study also shows that the passive films of both alloys are intact and not easily damaged by CE, with the LPBF TC4 alloy exhibiting a higher TiO₂ content and better corrosion resistance. The findings suggest that LPBF technology can improve the CE resistance of TC4 and extend its service life, facilitating the sustainable utilization and development of resources.This study compares the cavitation erosion (CE) and corrosion behavior of as-cast and laser powder bed fusion (LPBF) TC4 alloys in 0.6 mol/L NaCl solution. The LPBF TC4 alloy exhibited a rectangular checkerboard-like microstructure with a more refined grain size compared to the as-cast TC4. The LPBF TC4 showed significantly better CE resistance, with approximately 2.25 times lower cumulative mass loss after 8 hours of CE. The corrosion potential of both alloys decreased rapidly at the beginning of CE, but with prolonged CE time, a consistent negative shift in corrosion potential was observed, indicating a gradual decline in repassivation ability. The initial increase in corrosion potential during early CE stages was attributed to accelerated oxygen transfer. As CE progressed, the significant decrease in corrosion potential for both alloys was due to the breakdown of the passive film. The refined and uniform microstructure of LPBF TC4 effectively suppressed crack formation and propagation, highlighting the potential of LPBF technology in enhancing the CE resistance of titanium alloys. The study provides important insights into developing high-quality, reliable, and sustainable CE-resistant materials via LPBF technology. The results indicate that LPBF TC4 has superior CE resistance compared to as-cast TC4, with a more stable passive film and better corrosion resistance. The study also shows that the passive films of both alloys are intact and not easily damaged by CE, with the LPBF TC4 alloy exhibiting a higher TiO₂ content and better corrosion resistance. The findings suggest that LPBF technology can improve the CE resistance of TC4 and extend its service life, facilitating the sustainable utilization and development of resources.