  The domain wall problem and the isocurvature problem restrict possible
combinations of axion models and inflation models. In this paper, we considered
a new mechanism which solves those problems by dynamics of multiple scalar
fields during/after inflation. The mechanism makes axion models with a
non-trivial domain wall number compatible with inflation models with a large
Hubble parameter, $H_{I} \gg 10^{7\mbox{-}8}\,$GeV. The mechanism also avoids
the isocurvature problem. This mechanism increases the freedom of choice of
combinations of axion models and inflation models.
