  We have studied the neutral Higgs boson (NHB) contributions to the pure
penguin process $B\to \phi K_S$ in MSSM with middle and large $\tan\beta$ (say,
$>$ 8). We show that the $\alpha_s$ order hadronic matrix elements of NHB
induced operators can make sizable effects on both the branch ratio and time
dependent CP asymmetry $S_{\phi K}$. Under the all relevant experimental
constraints, the Higgs mediated contributions to $S_{\phi K}$ alone can provide
a significant deviation from SM and, in particular, lead to a negative $S_{\phi
K}$ which is reported by BaBar and Belle.
