  The minimal supersymmetric model with light sbottom ($\sim m_b$) and light
gluino (12 $\sim$ 16 GeV) can explain the excess of bottom quark production
cross section at hadron colliders and has drawn much attention. We calculate
one-loop contribution to Z-pole observable $R_b$ in this scenario when large CP
violating phases are allowed in the gluino mass and/or sbottom sector. We show
that these large CP violating phases can suppress the new contribution $\delta
R_b$ safely within the experimental bounds even for heavier sbottom too heavy
($\wt{b}_2 \gtrsim$ 200 GeV) to be produced at LEP2 in association with light
sbottom $\wt{b}_1$.
