  We explore the prospect of charged Higgs boson search in top quark decay at
the Tevatron collider upgrade, taking advantage of the opposite states of
$\tau$ polarization resulting from the $H^\pm$ and $W^\pm$ decays. Methods of
distinguishing the two contributions in the inclusive 1-prong hadronic decay
channel of $\tau$ are suggested. The resulting signature and discovery limit of
$H^\pm$ are presented for the Tevatron upgrade as well as the Tevatron$^\star$
and the Ditevatron options.
