The influence of Pr addition on the microstructure, phase transformation, and hardness of Ni₅₀Ti_50-xPr_x (x=0, 0.1, 0.3, 0.5, 0.7, 0.9, at%) shape memory alloys was investigated. Results show that Ni₅₀Ti_50-xPr_x alloys consist of NiTi matrix and NiPr precipi-tates. Ni₅₀Ti_49.5Pr_0.5 alloy has the optimal properties of martensitic transformation start temperature of 73 °C, the thermal hysteresis as narrow as 37 °C, and the Vickers hardness of 2850 MPa. Pr addition obviously decreases the martensitic transformation temperature of NiTi alloys, but the composite alloy maintains a relatively narrow thermal hysteresis and relatively high Vickers hardness, compared with other NiTi-based shape memory alloys.