Site occupancy of cations in spinel-type oxides is sometimes extremely difficult to solve by the conventional crystallographic analysis based on diffraction methods. The present report describes successful determination for manganese spinels by analyzing Kβ X-ray fluorescence spectra, which are essentially sensitive to chemical environments such as oxidation and/or coordination numbers. Instead of looking at peak positions and/or shapes of the spectra, the intensity ratios of Kβ′ satellite and Kβ 5 lines were investigated in detail. It has been found that the spectra are apparently classified depending on the manganese site occupancy whether tetrahedral A or octahedral B. Applications to some spinel-type oxides, for which the manganese states have not yet been fully solved so far, were also discussed.