  We present the next-to-leading order QCD corrected total cross sections and
the distributions of the transverse momenta of the final anti-bottom-quark,
top-quark and charged Higgs-boson for the processes of $p\bar p/pp \to t\bar b
H^-+X$ in the minimal supersymmetric standard model(MSSM) at the Tevatron and
the LHC. We find that the NLO QCD corrections significantly modify the
leading-order distributions of the transverse momenta of final
particles($p_T^b$, $p_T^t$ and $p_T^{H^-}$), and the total NLO QCD corrections
reduce the dependence of the cross section on the renormalization and
factorization scales, especially the NLO QCD corrected cross sections at the
LHC are nearly independent of these scales. Our results show that the relative
correction is obviously related to $m_{H^-}$ and $\tan\beta$, and the total NLO
QCD relative corrections can be beyond -50% at the Tevatron and approach -40%
at the LHC in our chosen parameter space.
