In present work, amorphous TiCuNi powders were fabricated by mechanical alloying process. Amorphization and crystallization behaviors of the TiCuNi powders during high-energy ball milling and subsequent microstructure changes were studied by X-ray diffraction and transmission electron microscope. TEM samples were prepared by the focused ion beam technique. The morphology of powders prepared with different milling times was observed by field-emission scanning electron microscope and optical microscope. The powders developed a fine, layered, homogeneous structure with milling times. The crystallization behavior showed that glass transition, $T_g$, onset crystallization, $T_x$, and super cooled liquid range ${Delta}T=T_x-T_g$ were 628, 755 and 127K, respectively. The as-prepared amorphous TiCuNi powders were consolidated by spark plasma sintering process. Full densified TiCuNi samples were successfully produced by the spark plasma sintering process. Crystallization of the MA powders happened during sintering at 733K.