Abstract: In this paper, we specialized parameters and argument, Hypergeometric function FE (1, 1, 1, 1, 2, 2; γ1, γ2, γ3; cosh x, cosh y, cosh z) FG, Fk and FN can be reduced to the hypergeometric function of Bailey’s F4(1, 2, γ2, γ3; -coshy, - cosh z) and also discussed their reducible cases into Horn’s function. In the journal we consider hypergeometric function of three variables and obtain its interesting reducible case into Bailey’s F4 & Horn’s function. In the section 2, hypergeometric function of four variables can be reduced to the hypergeometric function of one, two & three variables with some new and interesting particular cases.