  Non-decoupling effects of heavy new particles cannot be described by the
standard effective field theory with finite truncation of higher dimensional
operators. We propose a new effective field theory in which non-decoupling
quantum effects of new physics are correctly described. We discuss vacuum
stability and perturbative unitarity in our effective field theory, and we find
that the scale of new physics can be estimated if we will observe the Higgs
coupling deviation via non-decoupling effects in future collider experiments.
