  We investigate fractional quantum Hall effect at finite temperature using a
fermion Chern-Simons field theoretical approach. In the absence of impurity
scattering, the essential aspects of fractional quantum Hall effect, such as
the quantization of Hall conductance, as well as quasi-particle charge and
statistics are unrenormalized by thermal fluctuations. On the other hand, we
find that the low energy excitation spectrum at finite $T$ may undergo some
qualitative changes as temperature raises. Possible experimental consequences
are discussed.
