  The electroweak phase transition (EWPT) is considered in the framework of
3-3-1-1 model for Dark Matter. The phase structure within three or two periods
is approximated for the theory with many vacuum expectation values (VEVs) at
TeV and Electroweak scales. In the mentioned model, there are two pictures. The
first picture containing two periods of EWPT, has a transition $SU(3)
\rightarrow SU(2)$ at 6 TeV scale and another is $SU(2) \rightarrow U(1)$
transition which is the like-standard model EWPT. The second picture is an EWPT
structure containing three periods, in which two first periods are similar to
those of the first picture and another one is the symmetry breaking process of
$U(1)_N$ subgroup. Our study leads to the conclusion that EWPTs are the first
order phase transitions when new bosons are triggers and their masses are
within range of some TeVs. Especially, in two pictures, the maximum strength of
the $SU(2) \rightarrow U(1)$ phase transition is equal to 2.12 so this EWPT is
not strong. Moreover, neutral fermions, which are candidates for Dark Matter
and obey the Fermi-Dirac distribution, can be a negative trigger for EWPT.
However, they do not make lose the first-order EWPT at TeV scale. Furthermore,
in order to be the strong first-order EWPT at TeV scale, the symmetry breaking
processes must produce more bosons than fermions or the mass of bosons must be
much larger than that of fermions.
