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TiAl-based alloys have become the key material for the update of aerospace engineering. However, the coarse as-cast grain size, low room temperature plasticity and strength limit their further engineering application. In this paper, the Ti-48Al-2Cr-2Nb ingot alloyed with TiB2 and Ni was prepared by the induction melting and the effects of TiB2 and Ni on the solidification microstructure and mechanical properties were studied systematically. The results showed that the addition of TiB2 and Ni exhibited little influence on the solidification path and primary phase. The grain size was refined from 700 μm to 100 μm, and the flake TiB2 and Ni-riched τ3 phase was determined. The room temperature tensile strength of T4822-(Ni, TiB2) alloy was similar to that of the matrix alloy, and the fracture elongation was increased by 30%. At 700 ℃-900 ℃, T4822-(Ni, TiB2) alloy showed the preferable tensile strength, and the tensile strength at 900 ℃ reached 365 MPa, 9% higher than that of the matrix alloy. At 800 ℃ and 900 ℃, the breaking elongation reached 25.3% and 36.1%, respectively, much higher than that of the matrix alloy. The refinement of grain size and the block γ phase at grain boundary are the main reasons for the plasticity improvement of T4822-(Ni, TiB2) alloy, and the outstanding high temperature strength can be attributed to the borides and Ni-riched τ3 phase at the inner and interface of the lamellar colony.