Recent polar wind measurements between 5000 and 9000 km altitude by the Akebono satellite indicate that both H+ and O+ ions can have remarkably higher outflow velocities in the sunlit region than on the nightside. In addition, electrons also display an asymmetric behavior: the dayside difference in energy spread, greater for upward-moving than downward-moving electrons, is absent on the nightside. We use a self-consistent hybrid model [Tam et ai, 1995b] that was developed for the polar wind outflow to address these observed day-night asymmetric features. The model takes into account the evolution of the polar wind self-consistently by properly recognizing the global, kinetic, collisional effects of the sunlit photoelectrons. By studying the effects of the presence and absence of photoelectrons on the polar outflow, we compare the daytime and night-time polar wind results, and demonstrate the asymmetries observed by the Akebono satellite.