  Flavor changing neutral current processes in B and K decays in the
supergravity model are revisited taking into account the recent progress of
Higgs boson search experiments at LEP. Possible deviations of B^0--$\bar{B}^0$
mixing, the CP violating K^0--$\bar{K}^0$ mixing parameter $\epsilon_K$ from
the standard model predictions are reduced significantly in a small $\tan\beta$
region due to the constraints on the SUSY parameter space imposed by the Higgs
boson search. With the present bound on the Higgs boson mass, the magnitude of
the B^0--$\bar{B}^0$ mixing amplitude can be enhanced up to 12% for $\tanb=3$
in the minimal supergravity. If we relax the strict universality of SUSY
breaking scalar masses at the GUT scale, the deviation can be 25%. We also
investigate SUSY contributions to the muon anomalous magnetic moment in the
supergravity model and show that there is a correlation with the $b \to s
\gamma$ amplitude. The SUSY contribution to $a_\mu = \frac{(g-2)_\mu}{2}$ can
be (-30 -- $+80)\times 10^{-10}$ for $\tan\beta=10$ and even larger for larger
$\tan\beta$. The improved measurement of the muon anomalous magnetic moment in
the on-going experiment at BNL will put a strong constraint on SUSY parameter
space, especially for a large $\tan\beta$ region.
