  We summarize a discovery potential for supersymmetric particles at the \ppbar
collider of Tevatron with center-of-mass energy \sqrt{s} = 2 TeV and integrated
luminosity $\intlum$ = 15-30 \invfb. Any direct search is kinematically limited
to below 450 \mgev. We, however, have a unique opportunity to test various
supersymmetric scenarios by a measurement of the branching ratio for the rare
decay mode \bsmumu. Using the background estimate in the CDF analysis of
\bsmumu in Run I, we investigate the prospects for studying this mode in Run
II. CDF would be sensitive to this decay for a branching ratio > 1.2 \times
10^{-8} with 15 \invfb (or, if a similar analysis holds for \Dzero, >6.5\times
10^{-9} for the combined data). For \tanb > 30, the \bsmumu search can probe
the SUSY parameter space that cannot be probed by direct production of SUSY
particles at Run II. An observation of \bsmumu with a large branching ratio >
7(14) \times 10^{-8} (feasible with only 2 \invfb) would be sufficient to
exclude the mSUGRA model for \tan\beta \leq 50 (55) including other
experimental constraints. For some models, the branching ratio can be large
enough to be detected even for small $\tan\beta$ and large \mhalf.
