Photoemission studies of initial oxygen adsorption on the SiC (0001)-root3xroot 3 surface at different temperatures are reported. After exposures of 0.1 L to 10 L with the sample at room temperature or cooled to ca. 100 K structures appear in the 0 Is spectrum that are identified to originate from metastable oxygen. Adsorption of metastable molecular oxygen is suggested from the similarities obtained with earlier findings on Si (111)-7x7.