  CPT invariance in neutrino physics has attracted attention after the revival
of the hypothetical idea that neutrino and antineutrino might have nonequal
masses ($m_{\bar\nu} \neq m_{\nu}$) when realizing neutrino oscillations as a
new sensitive phenomenon to search for the violation of this fundamental
symmetry. Moreover, the profound relation between the CPT and Lorentz
symmetries turns the studies of CPT and Lorentz invariance violations into the
{\bf one two-sided} problem. We present a guide for non-experts through the
literature on neutrino physics. The basic works are reviewed thoroughly while
for the other papers only current results or discussion issues are quoted. The
review covers, mostly, oscillations of neutrinos, resonant change of their
flavors and cosmic neutrino physics to systematize possible evidences of
CPT/Lorentz violation in this sector of the Standard
