Ribbons of metal-metalloid glassy alloys (Fe,Cr)(80)(P,C,Si)(20) and Fe75Cr5P8C10Si2, respectively, were thermally treated at 480, 500 and 530 degrees C. After this oxidative glass treatment, the surface layer was characterized by ESCA. Only slight changes in the concentration of the elements as a function of treatment temperature and rime could be observed. The contents in oxygen, chromium and manganese (which exists as a trace element) rose weakly and contrarily the concentration of carbon and iron decreased. The results of the combined DTA-TG measurements of the glass sample in air showed negligible weight changes of the sample up to about 550 to 600 degrees C. The difference in the surface roughness between thermally treated and untreated samples could not be detected by scanning electron microscopy.