Let u : (M, g) → (N, h) be a map between Riemannian manifolds (M, g) and (N, h). The p-bienergy of u is defined by E p (u) = M |τ (u)| p dν g , where τ (u) is the tension field of u and p > 1. Critical points of E p (·) are called p-biharmonic maps. In this paper we will prove nonexistence result of proper p-biharmonic maps when p ≥ 2. In particular when M = R m , we get Liouville type results under proper integral conditions , which extend the related results of Baird, Fardoun and Ouakkas [1].