  The recently discovery of a massive neutron star (PSR J1614-2230 of
$1.97\pm0.04M_{\odot}$) rules out the soft equation of states (EOSs) such as
those included hyperons or kaon condensates at high densities, while the
nuclear theory or the terrestrial laboratory data prefer a soft EOS. Here we
propose one possible mechanism to allow that the observed massive neutron star
can be supported by a soft EOS, that is, if the the gravitational constant $G$
varies at super strong field, a soft EOS can support the massive neutron stars.
