This article presents the results of the research using the mothod of SAXS(small angle X-ray scattering) to investigate the influence of CH2Cl2, CHCl3 and CCl4 respectively on the liquid-crystal structure of phosphatidylcholine (PC). Experiments show the following phenomena: The structure of the PC liquid-crystal phase is primarily influenced by space-spinning electronic cloud density distribution of CH2Cl2, CHCl3 and CCl4. The compounds that their space-spinning electronic cloud density distribution assume spinning ball or spinning oval ball in shape all give the mechanism that makes the PC liquid-crystal state to form lamellar and hexagonal phase. And the compounds that their space-spinning electronic cloud density distribution assume spinning taper in shape give the mechanism that makes the PC liquid-crystal state to form hexagonal Ⅱ phase.