The results of cyclic oxidation tests at two temperatures of 1000 and 1100 degreesC are discussed for plain aluminide and slurry Si-modified coated Ni-base superalloy IN-738LC. Each cycle of 1000 degreesC oxidation test consisted of heating the samples in the stagnant air for 8 hours followed by cooling at room temperature for about 15 min. As for 1100 degreesC test the heating duration was I hr. The analyses of optical microscopy, SEM, EDS and XRD were utilized to characterize attack morphologies and phase changes of the coatings exposed to the test conditions. The tests revealed that the presence of Si in the aluminide coatings, in general, enhances cyclic oxidation resistance by delaying formation of harmful phases such as gamma'-Ni3Al (in coating layer) and NiO (in oxide scale).