The TC11 titanium alloy bar was subjected to solution aging treatment, and the relationship between the microstructure and impact properties of the alloy after solution aging treatment was studied by optical microscopy, XRD and impact performance testing. The results show that after the solution treatment in the two-phase region, the microstructure changes are small, and the β-transition structure appears in the structure after aging, and the α" phase is precipitated. After the solution treatment in the single-phase region, the primary α phase completely disappears, and the number of α" phases The grain boundary β phase appears; After solid solution in two-phase region, the microstructure consists of α phase and α′′ phase. After solid solution in single-phase region, the microstructure consists of α′ phase and α′′ phase. After aging treatment, the microstructure consists of α phase and β phase.; the impact toughness of the bar is the largest after solution treatment in the single-phase region, and the maximum value is 22 J /cm2, the impact toughness values of the two groups decreased with the increase of the aging temperature, but the decrease range was small; the crack propagation path after solid solution in the two-phase region was relatively gentle, and the crack path was deflected after aging, while the single-phase The crack propagation path after solid solution in the zone is more tortuous, and the crack after aging treatment is greatly deflected, and the propagation path is more tortuous.