  New physics contributions to B decays often arise through chromo-magnetic
penguin operators. To look for new physics effects in B decays, it is useful to
be able to estimate the hadronic matrix elements for the chromo-magnetic
operator. We compute this contribution to B ->phi K decays using PQCD methods.
It is shown that, if the Wilson coefficient of the new physics is same order of
magnitude as that of the Standard Model, this operator gives a non-negligible
contribution compared to that of the Standard Model (about 30%). We also
investigate the value of q^2, which is the momentum transferred by the gluon in
the chromo-magnetic penguin operator. We find that the expectation value <q^2>
is approximately M^2_B/4, in agreement with a naive guess. This result,
however, is very sensitive to the scale dependence of the Wilson coefficient.
We also show that the matrix element for the chromo-magnetic penguin operator
is independent of the choice of energy scale to a very good approximation.
