Analyses of hard X-ray resonant photoelectron emission spectroscopy (HAX-RPES) and related spectroscopies such as X-ray absorption spectroscopy (XAS) and resonant X-ray emission spectroscopy (RXES) are made for mixed valence Ce compounds with single impurity Anderson model. First, the spectra of Ce XAS ( XAS) and the conventional Ce 3d X-ray photoelectron emission spectroscopy (XPS) are analyzed for , taking into account the bulk/surface sensitivity in XPS. Then it is shown that the bulk properties are more directly obtained from the Ce 3d HAX-RPES spectra, in which the Ce 2p–5d excitation is followed by the Ce 2p3d5d Auger decay. Furthermore, the Ce 3d HAX-RPES can reveal some hidden structures in the Ce XAS. From the analysis of the Ce HAX-RPES for , we reveal the existence of the Ce contribution in the XAS, and confirm an important role of the Coulomb interaction between Ce 4f and 5d elctrons in the XAS structure. For ferromagnetic mixed valence Ce compound , the spectra of the XAS and its magnetic circular dichroism (MCD-XAS) are analyzed, and the effect of is also important in explaining the relative peak positions of the XAS and MCD-XAS. Finally, the MCD in RXES (MCD-RXES) is calculated for , and it is predicted theoretically that the excitation spectrum of MCD-RXES can also reveal the hidden structure of the configuration in the Ce XAS (and MCD-XAS) spectrum.