Three different kinds of closure model of fiber orientation tensors were applied to simulate numerically the hydrodynamic stability of fiber suspensions in a channel flow. The effects of closure models and three-dimensional (3-D) orientation distribution of fibers on the results of stability analysis were examined. It is found that the relationship of the behavior in hydrodynamic stability and the parameter of the fiber given by all the three models are the same. However, the attenuation of flow instability is most distinct using3-D hybrid model because the orientation of the fiber departures from the flow direction, and least apparent using its2-D counterpart for the the fibers show a tendency towards alignment with the flow direction in this case.