  We study the physical properties of the persistent charged current in a metal
ring on a noncommutative phase space, and temperature dependence of the
noncommutative corrections are also analyzed. We find that the coordinate
noncommutativity only affects the total magnitude of the current, and it is
difficult to observe it. In contrast, the momentum noncommutativity can violate
symmetry property of the current, and this violation of symmetry holds at a
finite temperature. Based on this violation effect, we introduce an asymmetry
observable to measure the momentum noncommutativity.
