Grand Unified Theories (GUTs) usually predict wrong Standard Model (SM)
fermion mass relation m_e/m_{\mu} = m_d/m_s toward low energies. To solve this
problem, we consider the Generalized Minimal Supergravity (GmSUGRA) models,
which are GUTs with gravity mediated supersymmetry breaking and higher
dimensional operators. Introducing non-renormalizable terms in the super- and
K\"ahler potentials, we can obtain the correct SM fermion mass relations in the
SU(5) model with GUT Higgs fields in the {\bf 24} and {\bf 75} representations,
and in the SO(10) model. In the latter case the gauge symmetry is broken down
to SU(3)_C X SU(2)_L X SU(2)_R X U(1)_{B-L}, to flipped SU(5)X U(1)_X, or to
SU(3)_C X SU(2)_L X U(1)_1 X U(1)_2. Especially, for the first time we generate
the realistic SM fermion mass relation in GUTs by considering the
high-dimensional operators in the K\"ahler potential.Comment: JHEP style, 29 pages, no figure,references adde