  Although the existence of Dark Matter (DM) has been suggested by various
astrophysical observations, it has not yet been discovered today. We can assume
a scenario in which the particles that account for the DM can interact with the
Standard Model particles only through their couplings with the Higgs sector,
the so-called Higgs-portal model. This model can be investigated by collider
experiment using the invisible decay of Higgs boson. In this study, we evaluate
the search ability of International Linear Collider (ILC) for invisible decay
of the Higgs using International Large Detector (ILD) full detector simulation.
We estimate 95% C.L. upper limit (UL) on the branching ratio of invisible Higgs
decays and compare them between two center-of-mass energy conditions: $\sqrt{s}
= 250$ GeV and 500 GeV. In addition, we describe the complementarity of lepton
collider experiment to the direct detection experiment about DM search ability.
