  We build an supersymmetric version of the minimal 3-3-1 model with just two
Higgs triplets using the superfield formalism. We study the mass spectrum of
all particles in concordance with the experimental bounds. At the tree level,
the masses of charged gauge bosons are the same as those of charged Higgs
bosons. We also show that the electron, muon and their neutrinos as well as
down and strange quarks gain mass through the loop correction. The narrow
constraint on the ratio t_w = \frac{w}{w^\prime} is given by studying the new
invisible decay mode of the Z boson.
