The morphology evolution of oxide scale formed on the (Ni,Pd)AI coating during oxidation in air at 900 similar to 1100degreesC was investigated systematically by scanning electron microscope and XRD. A long-term observation showed that the transformation of theta- to alpha-Al2O3 occurred on the (Ni,Pd)Al coating with increasing oxidation temperature and time. Furthermore, such transformation is more rapid on the (Ni,Pd)Al coating in comparison to a simple NiAl coating. In addition, the various morphologies for the theta-Al2O3 are also presented in this paper.