  We analyse the constraints of an Abelian 2-form gauge theory using
Faddeev-Jackiw symplectic formalism. Further, this theory is treated as a
constrained system in the context of Batalin-Fradkin-Vilkovisky formalism to
retrieve the BRST symmetry. Using the fields decompositions the effective
action for Abelian 2-form gauge theory is written in terms of diagonalized
uncanonical part and BRST exact one. The nilpotent BRST and contracting
homotopy $\sigma $ closed transformations with field redefinitions are shown as
the Darboux transformations used in the Faddeev-Jackiw formalism.
