The notions of coupled N-subalgebra, coupled (positive implicative) N-ideals of d-algebras are introduced, and related properties are investigated. Characterizations of a coupled N-subalgebra and a coupled (positive implicative) N-ideals of d-algebras are given. Relations among a coupled N-subalgebra, a coupled N-ideal and a coupled positive implicative N-ideal of d-algebras are discussed