  We calculate the one-loop QCD corrections to $t\rightarrow \tilde t_1 \tilde
\chi^0_j$ using dimensional reduction scheme, including QCD and supersymmetric
QCD corrections. The analytic expressions for the corrections to the decay
width are given, which can easily be extended to $t\rightarrow \tilde \chi^+_j
\tilde b_i $. The numerical results show that the correction amounts to more
than a 10\% reduction in the partial width relative to the tree level result.
We also compare the corrections in the no-mixing stop case with those in the
mixing stop case.
