The aim of this paper is to study a poset isomorphism between two support τ -tilting posets. We take several algebraic information from combinatorial properties of support τ -tilting posets. As an application, we treat a certain class of basic algebras which contains preprojective algebras of type A, Nakayama algebras, and generalized Brauer tree algebras. We provide a necessary condition for that an algebra Λ share the same support τ -tilting poset with a given algebra Γ in this class. Furthermore, we see that this necessary condition is also a sufficient condition if Γ is either a preprojective algebra of type A, a Nakayama algebra, or a generalized Brauer tree algebra.