The concept Tripolar fuzzy set is a generalization of bipolar fuzzy set, intuitionistic fuzzy set and fuzzy set. In this paper, the concept Tripolar fuzzy sub implicative ideals of KU-algebras are introduced and several properties are investigated. Also, the relations between Tripolar fuzzy sub implicative ideals and Tripolar fuzzy ideals are given. The image and the preimage of Tripolar fuzzy sub implicative ideals under homomorphism of KU-algebras are defined and how the image and the preimage of Tripolar fuzzy sub implicative ideals under homomorphism of KU-algebras become Tripolar fuzzy sub implicative ideals are studied. Moreover, the Cartesian product of Tripolar fuzzy sub implicative ideals in Cartesian product KU-algebras is established
