  We examine the time variation problem of solar neutrinos in the spin-flavour
precession mechanism taking into account the $\nu_e$-$\nu_{\mu}$ mixing. The
models with the small and large mixing angle are studied. It shows that the
models which realize $m_{\nu_e\nu_e} \sim m_{\nu_{\mu}\nu_{\mu}} \ll
m_{\nu_e\nu_{\mu}}$ and $m_{\nu_e\nu_e} \sim m_{\nu_{\mu}\nu_{\mu}} {^>_\sim}
m_{\nu_e\nu_{\mu}}$ seem to have preferable time variation features. It is very
interesting that the former type of models can give the large magnetic moment
to neutrinos and also suppress the radiative mass correction naturally.
