We report the x-ray absorption near edge structure (XANES) study on a series of Fe-Cr-O mixed oxide thin films with nominal composition Fe1-xCrxOy (x = 0.1 ~ 0.9). Fe and Cr L2,3-edge results indicate that Cr substitute Fe3+ at B-site preferentially for x ≦ 0.3. For x > 0.3 the spectral shape changes drastically indicating a possible structural change. Fe and Cr K-edge results indicate that the average valence of Fe and Cr are not changed for x ≦ 0.3. For x > 0.3, the average valence of both Fe and Cr increases systematically.