Abstract: The effect of different amounts (1, 2 and 3% wt.) of Ge additions on the corrosion behavior and microstructure of Cu-Al-Ni SMA were investigated by SEM, XR, EDS and electrochemical test. It was found that the microstructure and corrosion characteristics are highly sensitive to the composition changes. It was observed that the germanium addition controlled. The phase morphology along with the formation of Ge rich precipitates with copper which is (Cu Ge and CuGe). The corrosion behavior of the Cu-Al-Ni SMA before and 3 after the germanium addition were studied by electrochemical tests in 3.5% NaCl. solution. It was noticed that the corrosion rate of Cu-Al-Ni SMA in 3.5% NaCl was (34.99 mpy) and when added 3% Ge the corrosion rate decrease to become (4.72 mpy). This improved that the alloy containing higher amount of Ge has excellent properties than the base alloy. The confederation of XRD together with SEM and EDX showed that the corrosion products Ge4Na and Al2O3 represent as a protective layers which enhance the corrosion resistance of Cu-Al-Ni-Ge SMA.