This paper is a continuation of study by J. Ding and B.Feigin [1]. We find a bosonization of the deformed W -superalgebras Wqt(sl(2|1)) that commutes up-to total difference with deformed screening currents. Using our bosonization, we derive a set of quadratic relations of generators of the deformed W -superalgebra Wqt(sl(2|1)). The deformed W -superalgebra is independent of the choice of a Dynkindiagram for the superalgebra sl(2|1), though the deformed screening currents depend on it.