  Stimulated with the recent discovery of B-mode by BICEP2, we discuss the
relation between a Higgs inflation and a chaotic inflation with quadratic
potential. Starting with a generalized Higgs inflation model, we derive a
condition for obtaining the quadratic chaotic inflation. It is shown that the
running of the Higgs self-coupling constant in the Jordan frame plays a
decisive role when the generalized Higgs inflation model coincides with the
Higgs inflation model in a small-field limit.
