A recently proposed SO(5)xU(1) gauge-Higgs unification model in the Randall-Sundrum warped space contains a very interesting dark matter candidate, the Higgs boson. As a part of the fifth component of a five-dimensional gauge field, the four-dimensional neutral Higgs boson has odd H parity while all the other standard model particles have even parity to all orders in perturbation theory. Based on H-parity conserving WWHH and ZZHH vertices, we investigate the collider signatures of Higgs dark matter production associated with a SM W or Z gauge boson at the LHC and the ILC. The final state consists of a W or a Z boson with large missing energy. We found that the level of the signal cross section is quite hopeless at the LHC while we may be able to identify it at the ILC with polarized electron beams.

corrected and published version in Phys. Rev. D 81