Anodization of sputtered NiTi thin films has been studied in 1M acetic acid at 23°C for different voltages from 2 to 10V. The morphology and cross-sectional structures of the untreated and anodized surfaces were investigated by field emission scanning electron microscopy (FE-SEM). The results show that increasing anodization voltage leads to film surface roughening and unevenness. It can be seen that the thickness of the anodized layer formed on the NiTi surface is in the nanometer range. The corrosion resistance of anodized thin films was studied by potentiodynamic scan (PDS) and impedance spectroscopy (EIS) techniques in Hank's solution at 310K (37°C). It was shown that the corrosion resistance of the anodized film surface improved with increasing voltage to 6V. Anodization of austenitic sputtered NiTi thin films has also been studied, in the same anodizing conditions, at 4V. Comparison of anodized sputtered NiTi thin films with anodized austenitic shape memory films illustrate that the former are more corrosion resistant than the latter after 1h immersion in Hank's solution, which is attributed to the higher grain boundary density to quickly form a stable and protective passive film.