  We study the connection between monopoles and instantons in the Polyakov-like
gauge, and the behavior of the monopole trajectories generated by instantons at
finite temperature. The monopole trajectories become long and complicated at
the zero-temperature which can be regarded as monopole condensation. On the
other hand, they tend to become simple at finite temperature. It is suggested
that such a change is related to the confinement-deconfinement phase
transition.
