  We study the 0++ glueball correlator constructed with SU(3) anisotropic
quenched lattice QCD at various temperature taking into account the possible
existence of the thermal width in the ground-state peak. For this purpose, we
adopt the Breit-Wigner ansatz, analysing the lattice data obtained with
5,500-9,900 gauge configurations at each T. The results indicate the
significant thermal width broadening as Gamma(Tc) \sim 300 MeV with a reduction
in the peak center as Delta omega_0(Tc) \sim 100 MeV in the vicinity of the
critical temperature Tc.
