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Ti 2 AlNb alloys are expected to have applications in the aerospace field because of their excellent high-temperature performance and moderate density. Multi-wire arc-directed energy deposition (MWA-DED) technology enables the in-situ formation of Ti 2 AlNb alloys. However, Ti 2 AlNb alloys fabricated by MWA-DED face challenges such as compositional segregation and poor mechanical properties. In this study, high-performance Ti 2 AlNb alloys were efficiently prepared using MWA-DED technology, and their microstructure evolution was systematically analyzed. Hot-wire technology was proposed to assist in melting the TiNb wire to minimize the difference in the physical properties of the two wires. A pre-alloy droplet transfer mode with a large arc length was developed to eliminate composition segregation. The results showed that the Ti 2 AlNb alloys exhibited a homogeneous composition that matched the target Ti-22Al-23 Nb. Lots of strengthening phases (O phases higher than 90%) were precipitated throughout the sample. Temperature fields calculated from finite element simulation revealed that the precipitated phases were attributed to the "in-situ" heat treatment during deposition. The ultimate tensile strength and elongation reached 1002 MPa and 8% at room temperature, and 756 MPa and 8.3% at high temperature (650 ℃), respectively. The outstanding mechanical properties of Ti 2 AlNb alloys fabricated by MWA-DED are superior to those of cast and previously reported additively manufactured alloys. This study proposes novel ideas for additive manufacturing of high-performance Ti 2 AlNb alloys. [Display omitted] • Ti 2 AlNb alloys were efficiently in-situ manufactured by the multi-wire arc-directed energy deposition technique. • Hot-wire technology was proposed to eliminate the difference in physical properties of the two wires. • A pre-alloy droplet transfer model with high arc-length was explored to overcome compositional segregation. • Numerical simulations of heat transfer were developed to reveal the microstructure evolution mechanism. • High-performance Ti 2 AlNb alloys were obtained and the strengthening mechanisms were revealed. [ABSTRACT FROM AUTHOR]