The study of submanifolds with harmonic mean curvature vector field was initiated by B. Y. Chen in 1985 and arose in the context of his theory of submanifolds of finite type. For a survey on submanifolds of finite type and various related topics was presented in [8, 9]. Let M r be an n-dimensional, connected submanifold of the pseudo-Euclidean space E s . Denote by x⃗, H⃗, and △ respectively the ...