Abstract: Polyimide (PI) is widely used in low Earth orbit (LEO) spacecraft, but is vulnerable to atomic oxygen (AO) erosion. To address this issue, PI was blended with 5 wt% of Ti₃C₂T_x nanoparticles, and Ti₃C₂T_x/PI composite films were prepared using continuous centrifugal spraying technology. The AO erosion resistance of the films was evaluated under a simulated LEO environment. The results showed that the composite films maintained the original mechanical properties of PI films, while exhibiting significantly improved AO resistance, with an AO erosion yield of only 6.6% that of the PI films. These findings, confirmed by both experimental and molecular dynamics simulation, revealed that Ti₃C₂T_x reacts with AO to form a titanium oxide passivation layer, effectively protecting the material from further AO attack. The results demonstrate the potential of Ti₃C₂T_x/PI composite films as novel high-performance anti-AO erosion materials for LEO spacecraft applications.