Nowadays liquid crystals have widely used for optical devices, even are attractive in display. But a major problem for nematic phase is its long response time, which hinders the phase to be used in high quality displays. Surface Stabilized Ferroelectric Liquid Crystal¡]SSFLC¡^is a thin device which has fast response time and exhibits excellent bistability. It can be applied in display. But it is difficult for SSFLC to achieve alignment without zigzag defects. This defect will reduce contrast ratio of display and cause image irregularities and flickering. This article discusses zigzag defects in SSFLC device. In experiment, we use convenient rubbing method to alignment FLC with high pre-tilt PI film. And we investigate the surface properties of polyimide (PI) films rubbed with different rubbing strength. We fabricate the SSFLCs without zigzag defects, and confirm that the great rubbing strength produce more zigzag defects for FLC alignment. In addition, we discuss the topography of smooth surface results in fewer defects. Finally, with the relationship between surface energy and different rubbing strength in PI film, we show the polarity of surface energy is a important role for FLC alignment.