The $eta$-meson photoproduction cross sections have been measured on the C and Cu targets for the photon energies between 600 and 1100 MeV to investigate the behavior of the $S_{11}$(1535) resonance in a nucleus. The excitation functions of the cross section as well as the angular and momentum distributions of $eta$-mesons are in quantitative agreement with the Quantum Molecular Dynamics (QMD) model calculations in which the $eta$-meson emission processes other than the $S_{11}$(1535) resonance are also incorporated as proposed in the $eta$-MAID model. It is shown that the excitation of the $D_{15}$(1675) resonance might play an important role for $E_{gamma}>900$ MeV.
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