A liquid crystal (LC) alignment system includes an alignment film having a single or plurality of liquid crystal molecules aligned by a plurality of plasma generating devices, such that the liquid crystal molecules are aligned at a stable pretilt angle. Compared with the prior art, the present invention is suitable for modifying the alignment film surface by adjusting directions and angles of the liquid crystal molecules, and can attain the effect of alignment stability with a pretilt angle in a single process, thus overcoming the drawbacks of the prior art.