  We study Dirac fermionic dark matter (DM, $\chi^0$) and confront it with
recent data. To evade the stringent direct search limits from PandaX-II,
XENON1T and LUX experiments, the quantum numbers of the Dirac DM are taken to
be $I_3=Y=0$ to remove the tree-level $Z$-exchange diagram. Loop amplitudes can
contribute to the elastic scattering cross section. We find that there are
cancellations in the one-loop diagrams, which largely reduce the cross section
and make the Dirac DM viable in the direct search. For a generic isospin $I$,
we survey the Dirac DM mass constrained by the latest results of PandaX-II,
XENON1T and LUX experiments, the observed DM relic density, and the H.E.S.S.
and the Fermi-LAT astrophysical observations. Sommerfeld enhancement effects on
DM annihilation processes are investigated. We find that the cross section of
$\chi^0\bar\chi^0$ annihilating to the standard model (SM) gauge bosons are in
general significantly enhanced, and the Fermi-LAT, the H.E.S.S. upper limits on
$\langle\sigma v\rangle({W^+W^-,\gamma\gamma})$ and the observed relic density
become serious constraints on the Dirac DM mass. The $I<4$ cases are ruled out
and for $I\geq 4$, the lower bound on Dirac DM mass are forced to be $\gtrsim$
60 TeV. The elastic scattering cross section for $m_\chi$ of few tens TeV with
a generic $I$ is found to be $\sigma^{SI}\simeq
I^2(I+1)^2\times7\times10^{-49}$~cm$^2$. The predicted $\langle\sigma
(\chi^0\bar\chi^0\to Z^0Z^0, Z^0\gamma, \gamma\gamma)v\rangle$ and
$\sigma^{SI}$ are sizable and they will be useful to search for DM in
astrophysical observation and in direct search in near future.
