  Recently, the D0 collaboration reported a large CP violation in the same-sign
dimuon charge asymmetry which has the $3.2 \sigma$ deviation from the value
estimated in the Standard Model. In this paper, several new physics models are
considered: the MSSM, two Higgs doublet model, the recent dodeca model, and a
new $Z'$ model. Generally, it is hard to achieve such a large CP violation
consistently with other experimental constraints. We find that a scheme with
extra non-anomalous U(1)$'$ gauge symmetry is barely consistent. In general,
the extra $Z'$ gauge boson induces the flavor changing neutral current
interactions at tree level, which is the basic reason allowing a large new
physics CP violation. To preserve the U(1)$'$ symmetry at high energy,
SU(2)$_L$ singlet exotic heavy quarks of mass above 1 TeV and the Standard
Model gauge singlet scalars are introduced.
