  We investigate the observability of the lightest Higgs boson in the
gluon-fusion channel at the CERN Large Hadron Collider (LHC) in the minimal
supersymmetric Standard Model with explicit CP-violating mixing among three
neutral Higgs bosons. The lightest Higgs boson with its mass less than 130 GeV
can be detected at the LHC via its gluon-fusion production followed by the
decay into two photons. The explicit CP violation can suppress both the
production cross section and the two-photon decay branching fraction so
significantly that the signal cross section may be more than ten times smaller
than the SM signal. This reduction factor can be as small as 1/40 if the
lightest Higgs boson mass is 115 GeV and its production cross section at LEP2
is more than 90 % that of the SM case.
