  The Higgs-pair production process at the CERN Large Hadron Collider (LHC),
which will provide a way to test the Higgs boson self-coupling, may be
sensitive to new physics. In the framework of the littlest Higgs model with
T-parity, such Higgs-pair production can proceed through additional loop
diagrams and thus the production rate can be quite different from the Standard
Model (SM) prediction. Our calculations show that, due to the loop
contributions of both T-even and T-odd quarks predicted in this model, the
production rate can be significantly enhanced relative to the SM prediction and
also can be larger than the production rate in the minimal supersymmetric
model. Also, we find that the T-odd quark contributions, which were ignored in
a previous study, are equally important compared with the T-even quark
contributions.
