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The properties of pre-alloyed powder have an important influence on the additive manufacturing process, especially for Ti-Ni alloys with special shape memory effects. However, there are limited reports on the studies for the variation of Ti-Ni pre-alloyed powder with heat treatment temperatures and number of thermal cycles. In this work, the phase transformation behavior, microstructure and phase composition of 53~106μm Ti-Ni pre-alloyed powder used for electron beam melting (EBM) were studied using the differential scanning calorimeter, X-ray diffraction, scanning electron microscope. The results showed that the powder had good particle size distribution, internal filling and spherical topography, and suitable for EBM process. The structure and composition became uniform, internal stress and dislocation were eliminated and crystal grain size grown with the increase of heat treatment temperature, which caused the original multi-step phase transformation to one-step phase transformation during the heating and cooling process after 550 °C and the phase transformation points maintains a stable state after 650 °C. The phase composition not changed during the heat treatment process and the powder had best sintered state under 750 °C. The phase composition, one-step phase transformation behavior and phase transformation points were all not changed for the powder during 750 °C thermal cycles test, showed good thermal cycling stability. Ti-Ni solid samples with good surface condition were successfully prepared using EBM under 750 °C preheating temperature for bottom plate and powder layer.