  We present a theory of the Raman scattering from the orbital wave excitations
in manganese oxides. Two excitation processes of the Raman scattering are
proposed. The Raman scattering cross section is formulated by using the
pseudospin operator for orbital degree of freedom in a Mn ion. The Raman
spectra from the orbital wave excitations are calculated and their implications
in the recent experimental results reported in LaMnO$_3$ are discussed.
