The effect of thermal treatments at 750, 900 and 1000 o C on the microstructure and mechanical properties of a rapidly solidified Ni 3 Al-Cr alloy is reported. The microstructure of the ribbons in the as-rapidly solidified (RS) condition consisted of a partially ordered Ni 3 Al matrix and a fine Cr-rich second phase located at cell and grain boundaries. New and coarser α-Cr particles precipitated after annealing at 750 o C. No significant changes in the microstructure were observed for longer times. The α-Cr precipitates tended to dissolve in the Ni 3 Al matrix after annealing at 900 and 1000 o C. This dissolution seems to be controlled by the lattice Cr-diffusion in Ni 3 Al since the volume fraction of α-Cr particles decreased with increasing time and/or temperature of thermal treatments.The mechanical properties of the ribbons were influenced by the microstructural changes such as grain size, volume fraction and size of the α-Cr precipitates, that occurred during the annealing treatments. Thus, ribbons in the RS condition and after annealing at 750 o C were brittle however, they exhibited ductile behaviour after thermal treatments at 900 and 1000 o C.