We are concerned with the global behavior of the solutions of the focusing mass supercritical nonlinear Schrödinger equation under partial harmonic confinement.We establish a necessary and sufficient condition on the initial data below the ground states to determine the global behavior (blowup/scattering) of the solution.Our proof of scattering is based on the variational characterization of the ground states, localized virial estimates, linear profile decomposition and nonlinear profiles.